Police in Brussels killed a suspect armed with a Kalashnikov assault rifle during an anti-terror raid Tuesday that was linked to the November 13 attacks in Paris.
Three Belgian and one French police officer were injured when shots rang out during the two-country operation at an apartment in the suburb of Forest.
Since it was unclear whether other suspects remained at large late Tuesday, police operations were continuing.
The area was locked down for five hours after the initial burst of gunfire.
Belgian security forces have been actively hunting suspects and associates of the militants involved in the attacks that killed 130 people in Paris. The attacks were prepared and coordinated, in part, in Brussels.
Since mid-November, 11 people have been arrested and charged in Belgium in connection with the killings. Eight are still in detention.
One of the key suspects, Salah Abdeslam, 26, of Brussels, remains on the run. Belgian media quoted police as saying Abdeslam was not the target of Tuesday's raid.