Belgium has charged two more men yesterday with terrorist offences over alleged links to the rental of a property thought to have been used as a safe house before the Brussels attacks, according to Belgian federal prosecutors.

They identified the two men charged as Smail F., born in 1984, and Ibrahim F., born in 1988 and did not say when they were detained. Under Belgian law, suspects usually need to appear before an examining judge within 24 hours.

That brought to six the total of suspects caught and charged since late last week as a result of investigations since the March 22 bombings in Brussels that killed 32 people.

"They are charged with participation in the activities of a terrorist group, terrorist murders and attempts to commit terrorist murders, as a perpetrator, co-perpetrator or accomplice," federal prosecutors said of the latest two to be charged.

Police raided the suspected safe house in the central Brussels district of Etterbeek on Saturday, but found no weapons or explosives.

Belgian newspaper DH said the two men had been seen on security camera footage entering the house the day after the attacks and carrying out several bags. Prosecutors were not immediately available for comment on the DH report.

Four other suspects were arrested on Friday, including Mohamed Abrini, who investigators say has confessed to depositing a bomb at Brussels airport, and Osama Krayem, suspected of buying bags used by the bombers.

Abrini is also wanted in connection with November's attacks in Paris that killed 130 people.