A Belgian judge on Thursday ordered Mohamed Abrini and six other suspects arrested in connection with the attacks in Paris and Brussels kept behind bars for another month, prosecutors said.

Abrini has admitted being the "man in the hat" seen leaving Brussels Airport the morning of March 22, when two suicide bombers detonated explosives-laden suitcases there, killing 16.

Sixteen other people died that same morning when another bomber blew himself up on a Brussels subway train.

The Belgian Federal Prosecutors Office said Osama Krayem, a Swedish national suspected of being the accomplice of the Brussels subway bomber, was also ordered kept in preventive detention for another month, prosecutors said.

The others included four suspects charged in the Brussels attacks, and one man accused of helping key Paris attacks suspect Salah Abdemslam escape from France to Belgium.

Abrini, who was arrested in Belgium last week, also had close ties to the attackers who killed 130 victims on Nov. 13 in Paris, and is believed to have traveled to Syria and to have met with suspected Muslim extremists in England.

France's BFM television reported Abrini has claimed to investigators he "wouldn't hurt a fly."

Belgian and French authorities have detained dozens of suspects in their investigations of the attacks, which were claimed by Islamic State group extremists.