A report of a possible hostage-taking at the Montreal offices of French video game company Ubisoft that brought out a massive police response Friday was being investigated as a hoax, local media said.

Canadian broadcasters TVA and Radio-Canada cited unnamed police sources saying what had originally been reported as a hostage situation ultimately turned out to be a prank call from someone inside the building who'd demanded a ransom.

Police did not immediately confirm the reports, saying only in the early evening that the operation linked to the hostage-taking call was over.

"No threat has been detected and no injuries are reported. An investigation will follow to shed light on the call behind this important police force deployment," police said on Twitter.

Heavy police presence was seen by the Ubisoft office in Montreal in response to what local media said was a possible hostage-taking, but no threat had yet been found
Heavy police presence was seen by the Ubisoft office in Montreal in response to what local media said was a possible hostage-taking, but no threat had yet been found AFP / Andrej Ivanov

Ubisoft may have been the victim of a "swatting" prank, La Presse and Canadian channel TVA said.

The stunt, which involves a call to the police claiming an emergency at the target's premises, resulting in the arrival of armed officers, is popular among online gamers pranking rivals.

Investigators were looking at the possibility it was "the work of a 'gamer' unhappy with a new Ubisoft game having been designed in large part in Montreal," La Presse said. The perpetrators would have used the prank call to "take revenge" on Ubisoft, according to the online daily.

Authorities had announced on Twitter that the massive deployment started at about 1:30 pm, but offered few details while urging people to "avoid the area" near St-Laurent Boulevard and St-Viateur Street in Montreal's Mile-End neighborhood, close to downtown.

People are evacuated from the Ubisoft office in Montreal amid a major police operation in response to what local media said was a possible hostage-taking, but no threat had yet been found
People are evacuated from the Ubisoft office in Montreal amid a major police operation in response to what local media said was a possible hostage-taking, but no threat had yet been found AFP / Andrej Ivanov

About 100 staff were evacuated.

Television images showed the streets around the brick building cordoned off and heavily armed officers entering, as well as dozens of Ubisoft workers who appeared to have barricaded themselves on the rooftop.

A company employee reached by telephone told public broadcaster Radio-Canada that about 50 people were led to the rooftop terrace by managers who then barricaded the door leading to the stairwell with furniture.

Others were seen by an AFP journalist at the scene being escorted out of the front entrance.

"This is insane. This is my team on the roof," tweeted Ubisoft senior community developer Eric Pope, who was working from home.

Ubisoft is best known for video game titles such as Tom Clancy's Rainbow Six Siege, Far Cry and Assassin's Creed.

About 4,000 people would normally be working at its Montreal offices but many have been teleworking during the Covid-19 pandemic.