Brussels- Belgium’s Federal Investigation Judge decided to extend the detention of two people and to release unconditionally three others who were arrested by police early on Friday on suspicion of links to a terrorist group.

Belgian police arrested five people suspected of having ties with a terrorist group after swooping down on their homes in a Brussels suburb.

The prosecutor’s office said the arrests were related to a case not associated with Thursday’s attack in Paris.

Two of the four raids were conducted in Brussels’ infamous Molenbeek district, known for its predominantly Muslim and Arab population.

Police discovered a cache of weapons during the raids, which included two handguns, a bullet-proof vest, and ammunition.

The investigation bureau said that the order to extend the arrest was issued against two brothers.

While the arrests were made on the heels of the attack in Paris on Thursday, when a police officer was killed and two people were injured on the Champs Elysees, the prosecutor’s office stressed that the raids had been carried as part of a separate investigation, which is not related to the latest attack in France.

The suspects are not believed to have links to either the terrorist attacks in Paris of November 2015 or those on Brussels’ metro and Zaventem airport in March of 2016.

On the other hand, a Belgian man identified by the media as a potential second suspect in the murder of a French police officer on the Champs Élysées on Thursday night has no connection to the attack, according to two senior Belgian and French security officials.

Youssouf El Osri, 35, who turned himself in to police in Antwerp on Friday, was not suspected of involvement in the Paris attack but was brought to the attention of French authorities in relation to a drug investigation, said a senior Belgian law enforcement official.