PARIS - An armed man who earlier took several hostages at a post office northwest of Paris on Friday has surrendered with no one hurt, a French police official told Reuters.

The man equipped with a military weapon took an unconfirmed number of hostages at the post office in the town of Colombes, just outside the capital. ‘I cannot confirm or deny whether it is linked to terrorism,’ an official at the city prosecutor’s office told Reuters earlier, declining to give further details.

BFM TV, citing an unidentified source, said the hostage drama was not related to last week’s attacks in Paris. French police arrested 12 people earlier on Friday suspected of helping militant Islamist gunmen in last week’s killings in Paris. There have been numerous false alerts across the city since the attacks.

Moreover, Belgian, French and German police interrogated dozens of Islamist suspects on Friday as much of Europe remained on heightened security alert after last week’s killings in Paris and raids in Belgium in which two gunmen were killed.

In Paris there was a fresh scare when a gunman took several people hostage at a post office in a northwestern suburb. A siege ended when he gave himself up to police. No one was hurt. Authorities said they could not confirm whether the incident was related to terrorism.

Belgian police questioned 13 suspects and France held two people on Belgium’s request, a day after two gunmen were killed during raids against an Islamist group that authorities said were planning to attack police. French police said they had arrested 12 people suspected of helping the Islamist gunmen behind attacks last week on a satirical magazine and kosher supermarket in Paris.

Officials said there was no clear link between the suspected Belgian plot and the Paris attacks a week earlier, but described them as part of a common threat. ‘There is a terrorist offensive,’ French Prime Minister Manuel Valls told reporters. ‘We face the same threat.’ In Germany, police arrested two people following a raid on 12 homes and a mosque. A police spokesman said the suspects were probably part of an extremist cell that recruited fighters for Syria.

In Belgium, police uniforms, explosives and guns including four AK-47 assault rifles were found in the apartment where the two gunmen were killed on Thursday in the raid in the eastern town of Verviers. Their identities have not been released.