A YouTube prank went horrifically wrong when emergency crews had to rescue a man who had ‘cemented’ his head inside a microwave.

The bungling joker was trying to make a mould of his head in the bizarre stunt.

But it could have cost him his life, firefighters have said, after he became trapped.

The Pollyfilla mixture set faster than he expected, and his friends had to feed an air tube into his mouth to prevent him from suffocating, the Birmingham Mail reports.

Paramedics were called after his pals tried to free him for 90 minutes at a home in Wolverhampton, reports .

Ambulance workers alerted the fire service, and a crew spent an hour trying to free the trickster. Firefighters found him with the microwave still firmly stuck on his head, in the garage of a house in Fordhouses.

But it proved a mission impossible. In the end, they had to call colleagues from Technical Rescue for specialist advice.

The five-man crew then had to use a screwdriver to dislodge the Pollyfilla close to his head, eventually freeing him.

Watch Commander Shaun Dakin, who responded to the incident, said: ‘As funny as this sounds, this young man could quite easily have suffocated or have been seriously injured.

‘He and a group of friends had mixed seven bags of Polyfilla which they then poured around his head, which was protected by a plastic bag inside the microwave.

‘The oven was being used as a mould, and wasn’t plugged in, but the mixture quickly set hard.

‘By the time we were called, they’d already been trying to free him for an hour and a half.’

Watch Commander Dakin added: ‘Taking the microwave apart was tricky, because a lot of it was welded. We video-called our Technical Rescue colleagues for advice and eventually managed to get him unstuck.

‘He was very relieved when we removed a large chunk of the Polyfilla with a screwdriver, allowing him to breathe more easily. But we had to be extremely careful with the screwdriver, working so closely to his head.

‘It took us nearly an hour to free him. All of the group involved were very apologetic, but this was clearly a call-out which might have prevented us from helping someone else in genuine, accidental need.’