Paris attacks suspect Mohamed Abrini was arrested Friday, a police source told AFP after a Belgian television station said he was detained in a Brussels district.
At the same time prosecutors said police made several arrests in connection with the deadly Islamic State attacks on Brussels airport and metro last month.
The police source gave no details about the location or circumstances of Abrini's arrest but VRT television said it took place in the Anderlecht district of Brussels, home to several other suspects linked to the Paris attacks.
Abrini, a Belgian of Moroccan origin, was seen at a petrol station north of Paris two days before the attacks with key suspect Salah Abdeslam, who drove one of the vehicles used in the November 13 assaults across Paris that killed 130 people.
Abdeslam was supposed to have blown himself but did not do so, fleeing instead back to Brussels. He was arrested in Brussels on March 18 following a four-month manhunt and is being held in a high-security prison in the northern Belgian city of Bruges while awaiting his extradition to France.
The Belgian federal prosecutor's office said they would provide more details later about the arrests in connection with the Brussels attacks.
"The federal prosecutor confirms that there have been several arrests in the course of the day in connection with the attacks on the airport and metro," a statement said.
The attacks killed 32 people and wounded hundreds more.