The shootout broke out late on Tuesday afternoon in Brussels' southern neighborhood of Forest. The area, which is close to a factory of German car manufacturer Audi, has been secured.
Belgian broadcaster RTBF reported that one of three suspects was "neutralized," adding that it was unable to confirm whether the person had been killed or arrested.
Franco-Belgian operation
According to the federal prosecutor's office, four police officers were wounded during an initial search the property on Tuesday, while a fourth was hit by gunfire during the huge police mobilization which followed.
French Interior Minister Bernard Cazeneuve confirmed that French police were also involved in the operation, adding that the attackers used assault rifles.
Paris attacks
The raid on Tuesday came as Belgian police continued their hunt for Salah Abdeslam - a key suspect in last November's Paris attacks. Abdeslam and his associate Mohamed Abrini, both from the Molenbeek area of Brussels, are still at large. Belgian sources said, however, that Abdeslam was not the target of Tuesday's search.
Several anti-terror raids have been carried out across the country since Islamist militants carried out a series of attacks in the French capital on November 13, killing 130 people.

ksb/kms (AFP, AFP, dpa)