Belgian police officers in Molenbeek
Belgian police officers in MolenbeekReuters

Belgian authorities on Thursday arrested two men suspected of plotting a terrorist attack and charged them with terrorism offenses, federal prosecutors said, according to AFP.

The main suspect was arrested in the Brussels neighborhood of Molenbeek while his alleged accomplice was arrested near the northern Dutch-speaking city of Bruges, prosecutors said.

The men were charged with "participating in the activities of a terrorist group and preparing to commit a terrorist offence," spokesman Eric Van Duyse was quoted by AFP as having said.

Van Duyse added that the pair were not believed to have been plotting a "mass attack," but did not elaborate.

The prosecutor’s office said the pair were not Belgian nationals but did not give their nationalities.

It said the main suspect lived in the eastern French-speaking city of Liege, although he was arrested in the Brussels neighborhood of Molenbeek, which has been linked to terror activities in the past two decades.

Several terrorists who carried out attacks in Europe came from Molenbeek, including Abdelhamid Abaaoud, who was the mastermind behind the Islamic State (ISIS) attacks in Paris in November of 2015.

Police regularly detain terror suspects in the neighborhood.

A third suspect was detained in the eastern city of Leuven but was released after questioning, according to AFP.

Belgium has been on alert for extremist violence since the March 22, 2016 attacks on Brussels airport and a metro station left 32 dead and wounded hundreds of others.

Since January 10, Frenchman Mehdi Nemmouche has been on trial in Brussels on charges he murdered four people in a jihadist shooting spree at the Jewish museum in the Belgian capital.

Nemmouche’s lawyers claimed last week that he was not the killer. A man on trial as Nemmouche’s alleged accomplice, Nacer Bendrer, has also denied any connection to the attack.