Prosecutors initially said that four armed men had taken a captive at the property in a working-class area of the northwestern city, adding that there were no indications of terrorism.
"We are examining whether there was a hostage-taking," said Annemie Serlippens, the spokeswoman for the Ghent prosecutor, adding that reports of hostages were taken "very seriously" initially.
She said that the incident -- in which more than a dozen armed police officers set up a perimeter around the building -- appeared linked to drugs.
"But so far we have no indications of the presence of any Kalashnikovs or of armed people here," she said.
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"The presumed victim denied being taken hostage in the initial reports to police."
Public VRT Flemish-language television reported that three suspects had surrendered to police after leaving the building, but Serlippens said there had been no arrests.
A witness said a man came into her shop asking for help that morning.
Belgian authorities had earlier said there was no link to a hostage-taking going on at the same time in Sydney, Australia, where more than 20 people were held in a cafe.