Meanwhile, Belgium lowered the security threat level in Brussels on Thursday after nearly a week on maximum alert following the Islamic State attacks in Paris.
Belgian Prime Minister Charles Michel said that the threat of an attack in the city remained serious but was not as imminent as it had been.
He told a news conference that police and soldiers would remain on the capital's streets but that the metro, partially reopened on Wednesday after a four-day lockdown, would open in full from Friday morning.
"The situation is serious, but according to the indications of the security services, it is not as imminent as previously assessed," Michel said.
Immediately after the Paris attacks on Nov. 13, Belgium raised its security alert to Level 3 and a week later put Brussels onto maximum alert as police hunted a local suspect in the violence in France as well as accomplices who the government said might be planning similar attacks in the Belgian capital.
The suspect remains at large. Police have mounted a number of raids and searches over the past two weeks in Belgium, the most recent on Thursday, and have charged five people with terrorism offences linked to the Paris attacks.
Earlier Thursday, Belgian federal police mounted a raid on in a small town south of Brussels linked to fears of a militant attack, public broadcaster RTBF said, adding that officers were looking for weapons and explosives. RTBF said the information came from federal prosecutors.
A local police official in Sambreville told Reuters by telephone that an operation had been concluded but declined to say what the aim of it had been. A local government official referred all inquiries to the federal prosecutor in Brussels who is handling inquiries into the Nov. 13 attacks in Paris.
Federal police and prosecutors had no immediate comment. The raid was in Auvelais, part of the commune of Sambreville, the Belgian media reports said.
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