A manhunt is underway for the two escaped gunmen who are suspected of being connected to the November 2015 attack on Paris.
An Islamic State flag and a jihadist manual have been found at the scene of a Brussels anti-terror raid, according to prosecutors.
A spokesman said Belkaid had been living in Belgium illegally and was only known to the authorities because of a previous robbery incident.
Belkaid was unknown to Belgian authorities except for a case of theft in 2014, they said.
The sources said French police were part of that operation. Four officers were wounded in the exchange of fire, which lasted hours.
Local mayor Marc-Jean Ghyssels told public broadcaster RTBF that police searches in Forest were over: “The area is totally cleared, totally secured, and operations have ended”, he said.
Police came under fire the moment the flat’s door was opened by security forces during Tuesday’s search.
Among the fugitives is Belgian Salah Abdeslam, who fled the Paris attacks that night, slipped through a dragnet into Brussels and has not been seen since.
Police have also confirmed two other men are in custody, one of whom who is in hospital with a broken leg.
“In the short but intense shoot-out three of the six officers suffered slight injuries, amongst which a French female police officer”.
At a press conference on Wednesday, a spokesperson for the Belgian prosecutor’s office said a Kalashnikov, a book on Salafism and and an ISIS flag was found next to the body of the gunman killed by police.
The police intervention sparked a series of gun battles that also left children trapped in nearby schools.
“As soon as the agents rang the doorbell of the property, gunfire was direc- ted at them from inside”, said Mr Van Der Sijpt, who added that a Franco-Belgium team of officers was taken totally by surprise.
Abaaoud was killed during a dramatic raid that shook a Paris neighborhood and collapsed an entire floor of an apartment building.
Prime Minister Charles Michel said he was holding the state of alert steady after a meeting of security and intelligence chiefs in Belgium’s national security council.
Since the 13 November attacks, officials have identified most of the people they believe to have carried out the assaults – many of whom were based in Brussels.
More than 100 house searches have been conducted in Belgium in the context of the investigation and 58 people have been detained.