brussels attacks
Broken windows of the terminal at Brussels national airport. Yorick Jansens/ Reuters

Belgian police have arrested six people in Brussels in a series of anti-terror raids conducted in Brussels. The arrests come following investigations into the recent bombings at the airport and the Maelbeek metro station.

The Federal Prosecutor's office spokesman Eric van der Sypt said that there of the suspects were detained "outside the door of the federal prosecutor's office" in the centre of Brussels. Two others were arrested elsewhere in the city, the spokesman said.

Van der Sypt did not give further details on the arrests. "It will be decided tomorrow if an arrest warrant [charges] are brought against these people," he said.

Raids were also conducted in the district of Schaerbeek where the three airport attackers left from on 22 March morning carrying three explosive-packed suitcases, AFP news agency reported. There were no arrests made in the neighbourhood.

A total of 31 people were killed on 22 March at the Zaventem airport and the Maelbeek metro station. The attack on the metro was carried out by Khalid el-Bakraoui who self-detonated as the carriage pulled out of the station in the centre of the capital.

Police are now looking for another individual who is believed to have helped Khalid at the Metro station. According to the Belgian broadcaster RTBF reported that surveillance footage from Maelbeek has shown one man accompanying him carrying a large bag. It is not known whether this individual was killed in the attack or is on the run.

Khalid's brother Ibrahim and Isis bomb maker Najim Laachraoui set off the explosions at the airport. A third person pictured with them in the departure hall is now being sought by the authorities.