Four gunmen have entered a flat in the Belgian city of Ghent and police have sealed off the surrounding area.
Unconfirmed reports suggested that the four had taken a man hostage and police urged residents to remain indoors for their own safety.
The gunmen burst into the flat in the Dampoort area of the city, in northern Belgium.
“They’re in the building but it’s not clear what’s going on inside,” a police spokesman said.
The head of Ghent police Filip Rasschaert told De Standaard website that they were carrying out the operation carefully because of the potential involvement of a hostage.
Federal authorities were now in control of the siege, he said.
“They have all they need to bring a successful end to a hostage-taking,” he said.
Belgian TV said that another siege had taken place in Ghent in October, involving a man implicated in an earlier hostage-taking. That incident involved an unpaid debt, it reported.
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