Three armed men have given themselves up after entering an apartment in the Belgian city of Ghent, according to media reports.
Initial reports suggested four men entered the apartment and were holding one hostage, therefore the siege may be continuing.
The state prosecution service said there was no immediate indication that the incident was linked to terrorism and there was no further information about the four armed men.
Ghent police chief Filip Rasschaert told local outlet De Standaard authorities were conducting their operation with caution because of the possibility of a hostage inside the apartment.
"They have all they need to bring a successful end to a hostage-taking," he said.
"There is information that a hostage might have been taken, so we err on the side of caution."
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