Belgium on Tuesday charged a fifth suspect in connection with the Paris attacks, prosecutors said, as the capital Brussels was locked down for a fourth day under a state of maximum alert.

Belgian police on Monday had arrested five more people in a series of anti-terrorism raids in Brussels and the eastern city of Liege.

"The Investigating Judge, specialised in terrorism cases, has placed one person under arrest warrant for participation in the activities of a terrorist group and terrorist murders," a statement from Belgium's federal prosecutor said, adding that all the others had been released.