The 36-year-old was one of several suspects apprehended by Belgian police on Monday morning, after a series of raids were carried out across the country.

“The investigation concerns alleged facts of importation of cocaine from South America to Europe, via the port of Antwerp, and its redistribution in Belgium,” the Brussels prosecutor’s office said in a statement.

No further information has been released to the public.

The arrest comes just six days after Nainggolan came out of retirement to sign for Lokeren in the Belgian second division.

He scored on his debut, giving his side a point in their 1-1 home draw to K. Lierse.

Born in Antwerp, the midfielder spent most of his career in Italy, playing for both Roma and Inter Milan.

Between 2009 and 2018, he made 30 appearances for the Belgium national team.