Brussels: Armed Belgian police, with French support, were hunting one or more gunmen who wounded three officers during a raid on Tuesday in Brussels linked to the investigation of November's extremist attacks in Paris, officials said.
A southern section of the city was sealed off by police, Reuters journalists at the scene said. Police told residents to stay indoors and schools and kindergartens close to the scene of the shootings were in lockdown, residents said.
The mayor of the Brussels borough of Forest where the raid took place told Le Soir newspaper that one or more people had barricaded themselves into an apartment and that it was unclear how many others may be on the run.
Reuters journalists heard gunshots as police commandos crowded round the street where the raid had been carried out.
French Interior Minister Bernard Cazeneuve said French police units were also taking part in the raid in the Belgian capital, where investigators believe much of the planning and preparation for the November 13 IS attacks were carried out by young French and Belgians, some of whom fought in Syria.
"This operation is connected to the Paris attacks," a spokesman for Belgium's federal prosecutor told Reuters.
The area around the raid, near the main north-south railway linking Paris and Amsterdam and a car factory, was sealed off. A helicopter flew overhead and police commandos were deployed.
A spokeswoman for the local police service in southern Brussels said two officers were lightly wounded in an initial incident and a third was also slightly hurt later.
Belgian security forces have still been actively hunting suspects and associates of Brussels-based militants involved in the attacks in Paris in which 130 people were killed. Some of the attackers came from Brussels.
One of the prime suspects, 26-year-old Brussels-based Frenchman Salah Abdeslam, is still on the run. He left Paris shortly after his brother blew himself up in the attacks. Belgian authorities are holding 10 people who have been arrested in the months since the attacks, mostly for helping Abdeslam.
Belgian public broadcaster RTBF said that, according to French police sources, Abdeslam had not been the target of Tuesday's raid.
The Belgian capital, home of the European Union as well as Western military alliance NATO, was locked down for days after the Paris attacks on fears of a major incident there. Brussels has maintained a high state of security alert since then, with military patrols a regular sight.
Soldiers were on streets in central Brussels on Tuesday as the operation continued.