Video shows two inmates escaping from prison roof via helicopter in Canada

The escape happened at Quebec's St Jerome detention centre in 2013

Video footage has emerged showing the dramatic moment two inmates escaped from the roof of a Canadian prison via a hijacked helicopter – almost three years after the incident.

The astonishing clip was reportedly filmed by prison guards in Quebec in 2013 and has come to light during the unrelated trial of one of the two escapees, Benjamin Hudon-Barbeau.

Mr Hudon-Barbeau, and another prisoner, Danny Provencal, escaped from St Jerome detention centre in March 2013 aided by two accomplices, Billi Beaudoin and Steven Mathieu Marchisio, who hired the helicopter before hijacking it and forcing the pilot to fly to the prison at gunpoint.

In the video, Hudon-Barbeau and Provencal appear to have difficulty climbing onto the roof. They both cling to the rope, which is attached to the helicopter. As the chopper takes off, it carries the two inmates with it.

Speaking, at the time of the incident, Yves Galarneau, the correctional services manager who oversaw the Saint-Jerome jail, said he had never seen anything like it in more than three decades on the job.

Mr Galarneau added there were no security measures in place at the jail to stop a helicopter swooping down from above. "As far as I know it's a first in Quebec," he said. "It's exceptional."

CBC News reported that Hudon-Barbeau, Provencal and their accomplices were arrested just hours later. The union president of Peace Officers in Correctional Services of Quebec (SASPQC), Mathieu Lavoie, told Radio-Canada that guards were unable to interfere during the helicopter escape.

"We have to evaluate who's on board the helicopter — they were accomplices. Were they armed? We cannot intervene with inmates climbing a rope," he said. "It's only in the movies that you can shoot down a helicopter with a handgun."

According to AFP news agency, a New York businessman, Joel David Kaplan, used a helicopter to escape from a Mexican jail in 1971 and went on to write a book about the incident. Pascal Payet, a French prisoner, used a helicopter to escape on three occasions, only to be caught by authorities each time.