Streets around the house in a southern section of the city were sealed off by police, Reuters journalists at the scene said.
Belgium’s federal prosecutor said one or more people had barricaded themselves into an apartment after police had come under fire through a door when carrying out a raid. It was unclear whether others were on the run.
“This operation is connected to the Paris attacks,” a spokesman for Belgium’s federal prosecutor said.
A police spokeswoman said two officers were wounded in an initial incident and a third was also hurt later.
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.
Investigators believe much of the planning and preparation for the Nov. 13 Islamic State attacks were carried out by young French and Belgians, some of whom fought in Syria for Islamic State.
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.
Police told residents to stay indoors and schools and kindergartens close to the scene of the shootings were in lockdown, residents said.
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.
Brussels, 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.
Belgium, with a Muslim population of about 5 percent among its 11 million people, has the highest rate in Europe of citizens joining Islamist militants in Syria.