Passengers on an airliner watched in horror as a man set fire to a pornographic magazine at 30,000ft, a court heard.

David Mason, 45, used a lighter to torch handfuls of torn-up paper under his seat on the flight from Norway to Gatwick.

The mental health patient later claimed he was burning the pictures because they had "offended" him, Lewes Crown Court heard.

Mason admitted endangering the Boeing 737 jet and its passengers by acting in a reckless manner on February 12 this year.

Roger Booth, prosecuting, told how cabin crew on Flight BU595 from Bergen first became suspicious when Mason asked if he could incinerate some paper in the plane's galley oven.

They refused and sent him back to his seat.

Moments later, two concerned passengers on the jet, operated by Norwegian national airline Braathens, reported a smell of burning.

Cabin crew members then discovered that Mason, of Langley Avenue, Surbiton, Surrey, had started a small fire under his seat with a lighter. A stewardess poured water on the fire and managed to put it out before it spread, the court heard.

Mr Booth said: "It is a dangerous thing to do, to get a fire going on an aeroplane. It was only because the staff acted so promptly that the fire was put out quickly.

"When interviewed by police, Mason said he had bought some magazines and one showed a black man with a white woman and he had been offended by them.

"He said he was overcome and felt the desire to destroy them there and then."

Judge Richard Hayward adjourned the case until September 21 for a pre-sentence report.

He said: "If you light a fire on an aeroplane at 30,000ft then you are endangering that aircraft and its passengers.

"I feel an element of supervision is required to protect the public."

Matthew Butt, defending, said a change in Mason's medicine had led to his behaviour on the plane.