The unnamed men, all Norwegian citizens in their 20s with Iraqi heritage, were taken into custody in the Norwegian capital on Wednesday afternoon.

 lawyer Christian Hatlo told reporters the brothers were suspected of deliberately targeting the embassy with a powerful improvised explosive device (IED), with the intention of killing or causing serious harm.

None of the three had previously come to police attention.

Investigators believe one brother planted the bomb, while the other two played supporting roles in the plot. None had been questioned by the time of Wednesday’s news conference.

The blast struck in the early hours of Sunday morning, at the entrance to the embassy’s consular section in western Oslo.

A US official, speaking to The Associated Press news agency on condition of anonymity given the sensitivity of the investigation, said the device had been concealed inside a backpack.

Witnesses described the street filling with thick smoke following the explosion. There were no casualties. Police are examining whether the attack was carried out on behalf of a foreign government.

“We are still working from several hypotheses,” Hatlo said. “One of them is whether this is an order from a government entity; this is quite natural, given the target and the security situation the world is in today.”

A video uploaded to the embassy’s Google Maps page around the time of the blast, which was since removed, appeared to show Iran’s late Supreme Leader Ayatollah Ali Khamenei.

According to Norwegian public broadcaster NRK, the person who posted it wrote in Farsi: “God is great. We are victorious.”

Police have opened a separate investigation into the video.

‘Singled out’

Alireza Jahangiri, Iran’s ambassador to Norway, on Tuesday denied any involvement, saying in an interview with Norwegian newspaper Verdens Gang that it was “unacceptable” that Iran was “singled out”.

On Wednesday, Norway’s Justice Minister Astri Aas-Hansen welcomed the arrests, describing them as a breakthrough.

The country’s security service PST had warned as recently as last month that Iran, which it considers one of the principal threats to Norway, could use criminal networks as proxy actors to carry out operations on its behalf.

The attack comes as European nations remain on heightened alert following a series of incidents tied to escalating conflict in the Middle East, where US and Israeli forces have been conducting air strikes on Iran.

“Large resources” were sent to the area at about 01:00 local time (midnight GMT), police said.

“The police are in dialogue with the embassy and no injuries have been reported,” the statement said.

“There is currently no information about exactly what happened or who may be involved,” police added.

Michael Dellemyr, who is leading the police response, told Norwegian broadcaster NRK the explosion was at the public entrance to the building.

The embassy sustained minor damage, media reports say.

The US embassy is located in the Morgedalsvegen district of Oslo, about 7km (four miles) outside the city centre.

Arve Hjalmar Holmen has contacted the Norwegian Data Protection Authority and demanded the chatbot’s maker OpenAI is fined.

It is the latest example of so-called “hallucinations”, where artificial intelligence (AI) systems invent information and present it as fact.

Mr Holmen says this hallucination is damaging to him.

“Some think that there is no smoke without fire – the fact that someone could read this output and believe it is true is what scares me the most,” he said.

OpenAI says this case relates to a previous version of ChatGPT and it has since updated its models.

Mr Holmen was given the false information after he used ChatGPT to search for: “Who is Arve Hjalmar Holmen?”

The response he got from ChatGPT included: “Arve Hjalmar Holmen is a Norwegian individual who gained attention due to a tragic event.

“He was the father of two young boys, aged 7 and 10, who were tragically found dead in a pond near their home in Trondheim, Norway, in December 2020.”

Mr Holmen said the chatbot got their age gap roughly right, suggesting it did have some accurate information about him.

Digital rights group Noyb, which has filed the complaint on his behalf, says the answer ChatGPT gave him is defamatory and breaks European data protection rules around accuracy of personal data.

Noyb said in its complaint that Mr Holmen “has never been accused nor convicted of any crime and is a conscientious citizen”.

ChatGPT carries a disclaimer which says: “ChatGPT can make mistakes. Check important info.”

Noyb says that is insufficient.

“You can’t just spread false information and in the end add a small disclaimer saying that everything you said may just not be true,” Noyb lawyer Joakim Söderberg said.

OpenAI said in a statement: “We continue to research new ways to improve the accuracy of our models and reduce hallucinations.

“While we’re still reviewing this complaint, it relates to a version of ChatGPT which has since been enhanced with online search capabilities that improves accuracy.”

Hallucinations are one of the main problems computer scientists are trying to solve when it comes to generative AI.

These are when chatbots present false information as facts.

Earlier this year, Apple suspended its Apple Intelligence news summary tool in the UK after it hallucinated false headlines and presented them as real news.

Google’s AI Gemini has also fallen foul of hallucination – last year it suggested sticking cheese to pizza using glue, and said geologists recommend humans eat one rock per day.

It is not clear what it is in the large language models – the tech which underpins chatbots – which causes these hallucinations.

“This is actually an area of active research. How do we construct these chains of reasoning? How do we explain what what is actually going on in a large language model?” said Simone Stumpf, professor of responsible and interactive AI at the University of Glasgow.

Prof Stumpf says that can even apply to people who work behind the scenes on these types of models.

“Even if you are more involved in the development of these systems quite often, you do not know how they actually work, why they’re coming up with this particular information that they came up with,” she told the BBC.

ChatGPT has changed its model since Mr Holmen’s search in August 2024, and now searches current news articles when it looks for relevant information.

Noyb told the BBC Mr Holmen had made a number of searches that day, including putting his brother’s name into the chatbot and it produced “multiple different stories that were all incorrect”.

They also acknowledged the previous searches could have influenced the answer about his children, but said large language models are a “black box” and OpenAI “doesn’t reply to access requests, which makes it impossible to find out more about what exact data is in the system.”

For more than 75 years Oslo-based car dealership Harald A Møller has been importing Volkswagens, but early in 2024 it bid farewell to fossil fuel cars.

Now all the passenger vehicles for sale in its showroom are electric (EV).

“We think it’s wrong to advise a customer coming in here today to buy an ICE [internal combustion engine] car, because the future is electric,” says chief executive Ulf Tore Hekneby, as he walks around the cars on display. “Long-range, high-charging speed. It’s hard to go back.”

On the streets of Norway’s capital, Oslo, battery-powered cars aren’t a novelty, they’re the norm. Take a look around and you’ll soon notice that almost every other car has an “E” for “electric” on its license plate.

The Nordic nation of 5.5 million people has adopted EVs faster than any other country, and is on the cusp of becoming the first to phase out the sale of new fossil fuel cars.

Last year, the number of electric cars on Norway’s roads outnumbered those powered by petrol for the first time. When diesel vehicles are included, electric cars account for almost a third of all on Norwegian roads.

And 88.9% of new cars sold in the country last year were EVs, up from 82.4% in 2023, data from the Norwegian Road Federation (OFV) showed.

In some months sales of fully electric cars were as high as 98%, as new petrol or diesel car purchases almost fizzled out.

By contrast, in the UK electric cars made up only 20% of new car registrations in 2024. Although this was a record high, and up from 16.5% in 2023.

In the US, the figure was just 8% last year, up from 7.6%.

Norway is undoubtedly an EV pioneer, but this electric revolution has been three decades in the making.

“It started already in the early 1990s,” says Christina Bu, the secretary general of the Norwegian EV Association, as she took me for a spin around Oslo in an electric minivan.

“Little by little taxing petrol and diesel engine cars more, so they have become a lot more expensive to purchase, whereas electric cars have been exempted from taxes.”

The support for electric vehicles was first introduced to help two Norwegian manufacturers of early EVs, the Buddy (previously Kewet) and TH!NK City. While they went out of business, the incentives for greener vehicles remained.

“It’s our goal to see that it’s always a good and viable choice, to choose zero emission,” says Norway’s Deputy Transport Minister, Cecilie Knibe Kroglund.

Even though it’s a major oil and gas producer, Norway aims for all new cars sold to be “zero emission”, starting at some point in 2025. A non-binding goal was set back in 2017, and that milestone now lies within reach.

“We are closing up on the target, and I think that we will reach that goal,” adds Kroglund. “I think we have already made the transition for passengers cars.”

Key to Norway’s success has been long-term and predictable policies, she explains.

Rather than banning combustion engine vehicles, the government has steered consumer choices. In addition to penalising fuel fossil vehicles with higher taxes and registration fees, VAT and import duties were scrapped for low-emission cars.

A string of perks, like free parking, discounted road tolls and access to bus lanes, then followed.

By comparison, the European Union plans to ban sales of new fossil-fuel cars by 2035, and the UK’s current government wants to prohibit their sale in 2030.

Petrol and diesel car sales are still permitted in Norway. But few are choosing to buy them.

For many locals, like Ståle Fyen, who bought his first EV 15 months ago, going electric made economic sense.

“With all the incentives we have in Norway, with no taxes on EVs, that was quite important to us money wise,” he says while plugging in his car at a charging station in the capital.

“In the cold, the range is maybe 20% shorter, but still, with the expansive charging network we have here in Norway, that isn’t a big issue really,” Mr Fyen adds. “You just have to change your mindset and charge when you can, not when you need to.”

Another driver, Merete Eggesbø, says that back in 2014 she was one of the first people in Norway to own a Tesla. “I really wanted a car that didn’t pollute. It gave me a better conscience driving.”

At Norwegian petrol stations many fuel pumps have been replaced by fast-charging points, and across Norway there are now more than 27,000 public chargers.

This compares with 73,699 in the UK – a country 12 times bigger in terms of population.

That means that, per 100,000 people, Norway has 447 chargers while the UK has just 89, according to a recent report.

Tesla, VW and Toyota, were Norway’s top-selling EV brands last year. Meanwhile, Chinese-owned marques – such as MG, BYD, Polestar and XPeng – now make up a combined 10% of the market, according to the Norwegian Road Federation.

Norway, unlike the US and EU, has not imposed tariffs on Chinese EV imports.

Ms Bu says there’s “not really any reason why other countries can not copy Norway”. However, she adds that it is “all about doing it in a way that can work in each country or market”.

Norwegians aren’t more environmentally-minded than people elsewhere, she reckons. “I don’t think a green mindset has much to do with it. It has to do with strong policies, and people gradually understanding that driving an electric car is possible.”

Yet Norway is also a very wealthy nation, which thanks to its huge oil and gas exports, has a sovereign wealth fund worth more than $1.7tn (£1.3tn). This means it can more easily afford big infrastructure-build projects, and absorb the loss of tax revenue from the sale of petrol and diesel cars and their fuel.

The county also has an abundance of renewable hydro electricity, which accounts for 88% of its production capacity.

“A third of cars are now electric, and it will pass 50% in a few years,” says Kjell Werner Johansen from the Norwegian Centre for Transport Research. “I think the government accepts that a few new petrol or hybrid cars will still be on the market, but I don’t know anybody who wants to buy a diesel car these days.”

The move was blocked after the country’s Socialist Left Party said it would not support the government’s budget unless it scrapped the first licensing round, set for 2025.

Environmental scientists had warned the move could be catastrophic for marine life, while the plans were opposed by 32 countries including France, Canada, Brazil and Germany.

Prime Minister Jonas Gahr Stoer called Sunday’s development a “postponement” and said preparatory work on regulations and environmental impact would continue.

Greenpeace Norway’s Haldis Tjeldflaat Helle said the pause was “a huge win”.

“It has been truly embarrassing to watch Norway positioning itself as an ocean leader, while planning to give green light to ocean destruction in its own waters.”

The country’s energy ministry has not yet commented.

Norway became the first country in the world to move forward with commercial-scale deep-sea mining when it approved the plans in January.

The deep sea is home to minerals such as lithium, scandium and cobalt – which are critical for green technologies.

Although the metals are available on land, they are concentrated in a small number of countries, increasing the risk to supply.

Oslo said it did not want to rely on China for such materials, stressing it would only begin issuing licences once more environmental research was carried out.

The move put Norway at odds with the EU and the UK, which have called for a temporary ban on the practice due to concerns about environmental damage.

More than 100 EU lawmakers called on Oslo to reject the project, citing the risk “to marine biodiversity and the acceleration of climate change”.

The country’s Institute of Marine Research criticised the government’s research into the move’s environmental impact – saying five to 10 more years of work were needed.

The World Wide Fund for Nature (WWF) Norway said in a statement last week it was suing the government over the plans.

At least three Norwegian seabed mineral start-ups had said they would bid in the first licensing round.

On Monday, one of the start-ups – Green Minerals – said it expected a delay of up to a year following the plans’ suspension.

Marius Borg Høiby, 27, is the stepson of the heir to the Norwegian throne, Crown Prince Haakon, but does not a have a royal title or official duties.

On Tuesday, Norwegian police said Mr Høiby had been charged with sexual intercourse with “someone who is unconscious or for other reasons is unable to resist the act”.

Mr Høiby, who has reportedly denied the rape allegation, is facing a number of charges for offences allegedly committed against four other victims.

In a statement, police said the rape “concerns [a] sexual act without intercourse” and that the victim was “said to have been unable to resist the act”.

According to local reports, the Norwegian palace has declined to comment on the latest arrest of Mr Høiby.

Mr Høiby was arrested by police at 23:12 (22:12 GMT) on Monday in a car with a victim from a separate incident.

In relation to this separate incident, on 4 August, he faces charges of violence and criminal damage.

Police said on Tuesday that the charges had been expanded to include “maltreatment” in close relationships and “another violation” of a restraining order against the same victim.

They added that a report had been made for driving without a valid driver’s licence.

Mr Høiby’s residence at Skaugum, close to where the crown prince and his wife live, has also been searched by police.

Mr Høiby has also previously been charged with abuse against ex-girlfriends Julianne Snekkestad and Nora Haukland, as well as with threatening a man.