Belgium lowered the terror alert from level 4 to 3 in the capital Thursday, five days after it was raised to the highest possible level, the government's crisis center announced.
Brussels remains on high alert, however, following a four-day security lockdown, during which schools and the metro were closed. The security measures were taken because of fears that French and Belgian militants would carry out more terrorist attacks like the one in Paris on November 13.
Belgian authorities have been pursuing a Brussels man suspected of participating in the Paris violence and possible accomplices. Five people were arrested on terrorism charges.
The police conducted a raid around noon Thursday in the municipality of Sambreville, 80 kilometers south of Brussels and close to the French border, but did not detain anyone. The federal prosecutor’s office said it was part of investigations into the Islamic State's attack in Paris, but did not give further details.
Police also launched two more raids in Verviers, 125 kilometers east of the capital.
In a related development, Belgian fire crews and decontamination teams evacuated a major mosque in Brussels after receiving an envelope with white powder, suspected to be anthrax, but later a senior fire official said it turned out to be harmless.