All I can say is it must've been one hot film!

A man is fighting for his life with third degree burns over 90 per cent of his body after catching fire in a pornography shop.

Police say the man had been watching adult videos in one of the Golden Gate Adult Superstore private booths in San Francisco when the fire ignited.

He is said to have run screaming from the booth to outside the store engulfed in flames before he collapsed.

A San Francisco Fire Department spokesman said police officers across the street from the shop were alerted to the incident when they saw a man run out of it about 6pm on Wednesday.

They managed to extinguish the flames before transporting him to St Francis Memorial Hospital's Bothin Burn Center.

He is said to be fighting for his life after suffering burns ranging from first to third-degree to more than 90 percent of his body.

Scene: A fire fighter examines the charred debris left behind by the man who bust into flames in the San Francisco porn shop

Clothing: The jeans and shoes of the man who caught fire which had to be cut off his body by fire fighters remain at the scene

Arson investigators have said they are unsure how the man caught fire.

Lieutenant Kevin McNaughton told CBS San Francisco news: 'At 6:10 this afternoon at the corner of 6th and Mission Street, a man was running out of the adult arcade right behind me that was totally engulfed in flames. Police officers that were immediately across the street called it in.'

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