The tourists – two Australians, two Danes, an American and a British national – died earlier this month after apparently drinking tainted alcohol in the town of Vang Vieng. Several were staying at the Nana Backpacker Hostel.

It is unclear how many other people were taken ill.

The deaths have cast a spotlight on the popular backpacking town and spooked tourists, especially women, as five of the six who died were female travellers.

Several governments, including New Zealand, Australia, and the UK, have warned their citizens about drinking spirits in Laos.

Last week, 19-year-old Australians Bianca Jones and Holly Bowles died days after being admitted to hospital in neighbouring Thailand.

Theirs were the first deaths suspected to be caused by methanol, a toxic, flavourless and colourless substance commonly added to bootleg alcohol.

Then Danish authorites reported the deaths of two women, aged 19 and 20, who had died in Vang Vieng earlier this month. A 57-year-old American man was also found dead in Vang Vieng.

And last week, a 28-year-old London lawyer, Simone White, died after she was believed to have ingesed methanol.

The owners of the Nana Backpackers hostel, which is now closed, had denied serving illicit alcohol.

Some travellers in Vang Vieng are steering clear of the once-popular free shots and alcohol buckets offered to tourists. They are concerned about their safety.

Methanol poisoning is the most prevalent in Asia, mostly affecting poorer communities and places with weak food regulations and enforcement.

A New Zealander who had fallen ill from suspected methanol poisoning in the country has now returned home, authorities have confirmed.