Belgian authorities said Tuesday they have taken into custody four alleged accomplices in the Paris terror attacks and issued an alert for a fifth suspect who they said was dangerous and probably armed.

Most of the men are charged with helping Salah Abdeslam, who is the subject of an international manhunt. His name was on rental documents for a Belgian-registered black Volkswagen Polo found outside the Bataclan concert hall, where 89 people were killed.

Salah is the brother of Brahim Abdeslam, one of the dead attackers, officials have said.

Belgian authorities released a photo of Mohamed Abrini, a suspect in the Paris terrorist attacks. Belgian Federal Police

The Belgian Federal Public Prosecutor's Office said it had arrested Amri Mohammed and Attou Hamza, who investigators say gave Abdeslam a ride back to Belgium the morning after the attacks in a Volkswagen Golf. A third man, a 31-year-old French national identified only as Ali O., for allegedly giving Abdeslam a ride later on, the prosecutor's office said.

Authorities said Ali O. lived in the Molenbeek area of Brussels, where much of the investigation has focused.

The Nov. 13 attackers were French and Belgian, and the man suspected of organizing the attacks, 27-year-old Abdelhamid Abaaoud, grew up in Molenbeek. He was killed during a raid in the Paris suburb of Saint-Denis.

Abdeslam and his dead brother, both French nationals, lived in Molenbeek, authorities said.

The prosecutor's office said it had also arrested a 39-year-old Moroccan from Molenbeek, whom they identified as Lazez A. The office did not say how it thought he was involved in the attacks, but noted that investigators had found two guns and "traces of blood" in his car.

All of those arrested are charged with participation in the activities of a terrorist group and terrorist murders.

The announcement also included an alert for a man believed to have traveled to Paris with Abdeslam two days before the attacks. The prosecutor's office said Mohamed Abrini as caught on film with Abdeslam in a gas station on the highway to Paris. Abrini, 30, was driving a Renault Clio later used by the attackers, prosecutors said.

Authorities have issued an arrest warrant for Abrini, the prosecutor's office said.

France has taken 165 people into custody and indicted 124 since the attacks, the country’s interior minister said on Tuesday.

Security officials have also conducted 1,233 searches and seized close to 200 arms — including "weapons of war" such as automatic rifles and explosives, French Interior Minister Bernard Cazeneuve told parliament.

Cazeneuve didn't say what the indictments were related to or whether they were directly linked to the attacks.

Belgium, meanwhile, has placed its capital of Brussels on highest alert, with Prime Minister Charles Michel citing a "serious and imminent threat" to the city which is home of the headquarters of the European Union and NATO.

European officials were working feverishly on numerous fronts to stave off potential terror attacks while chasing leads from the latest one. Police raids in Europe thus far have failed to capture the primary person-of-interest in the Paris terror attacks: Salah Abdeslam.