Two people have been killed after Belgian police raided a terrorist cell in the east of the country.
Witnesses reported hearing explosions and gunfire near a train station in the Verviers region.
Magistrate Eric Van der Sypt told reporters in Brussels today that the suspects were on the verge of committing a major terrorist attack, and that they immediately opened fire on security forces.
He said at emergency news conference that anti-terrorist raids are under way in the Brussels region and Verviers.
He said Belgium's terror alert level was raised to its second highest level.
The raid was part of an investigation into extremists returning from Syria.
Belgian authorities are looking into possible links to attacks in neighbouring France last week that killed 20 people, including three gunmen who attacked satirical newspaper Charlie Hebdo, a kosher supermarket and police.
Witnesses speaking on Belgium's RTBF radio described a series of explosions followed by rapid fire at the centre of Verviers, near a bakery and in the area of the train station. Video posted online of what appeared to be the raid showed a dark view of a building amid blasts, gunshots and sirens, and a fire with smoke billowing up.
RTBF said two people were killed during the raid in Verviers, a former industrial town with a large immigrant population about 80 miles) southeast of the capital, Brussels. Flemish broadcaster VRT said two were killed, one injured and one arrested.
Earlier today, Belgian authorities said they were looking into possible links between a man they arrested in the southern city of Charleroi for illegal trade in weapons and Amedy Coulibaly, who prosecutors say killed four people in a Paris kosher market last week.
The man arrested in Belgium "claims that he wanted to buy a car from the wife of Coulibaly," said federal prosecutor's spokesman, Eric Van der Sypt. "At this moment this is the only link between what happened in Paris."
Van der Sypt said that "of course, naturally" we are continuing the investigation.
At first the man came to police himself claiming there had been contact with Coulibaly's common law wife regarding the car, but he was arrested following a search on his premises when enough indications of illegal weapons trade were found.
Van der Sypt stressed there was no established weapons link with the Paris attack at this moment.
Several countries are now involved in the hunt for possible accomplices to Coulibaly and the two other gunmen in the French attacks.
