The key suspect in November's Islamic State attacks in Paris, Mohamed Abrini, has been arrested in Brussels, Belgian media said today.

Abrini was also likely to have been involved in last month's Brussels bombings. He was "more than likely" the "man in the hat" seen on CCTV before the blast, said Belgian public broadcaster VRT, citing unidentified sources.

Public prosecutors confirmed in a brief statement only that police had made several arrests related to the Brussels attacks.

A second suspect, believed to have been seen with a third suicide bomber on the metro, was also held.

VRT named the second man as Osama Krayem. It gave no other details.

Abrini has been on Europe's most wanted list since being identified on CCTV video in a car with Salah Abdeslam, the recently arrested prime surviving Paris suspect, two days before the November 13 attacks in the French capital.

The "man in the hat" left the airport shortly after the twin suicide bombing in Brussels and was tracked on CCTV for several miles into the city centre. On Thursday, investigators released new video footage of him appealing for the public's help in finding him.

Wearing glasses and a hat, he had been very difficult to identify from the footage showing him pushing a laden luggage trolley alongside the two men who would blow themselves up with similar explosive bags. A third bomb was later found abandoned at the airport.

Abdeslam was arrested in Brussels two weeks ago, four days before Islamic State suicide bombers struck in the city.

Abrini has a criminal record, having been convicted in Belgium several times for robbery and violence.

Additional reporting by Reuters.