A biochemistry student who died during a human catapult event is thought to have narrowly missed falling into a safety net the size of a tennis court.

A participant tries out the catapult before the tragic accident

Kostadin Yankov, 19, a first year student at Oxford University's Wadham College, had joined 20 members of extreme-sports club The Oxford Stunt Factory, to try human catapulting at Middlemore Water Park in Woolavington, near Bridgewater, Somerset, on Sunday.

Six people were catapulted successfully across disused land at the park.

But the Bulgarian student just missed the net and suffered serious injuries. He was airlifted to Frenchay Hospital, in Bristol, and died at about 7.30pm.

Police and the Health and Safety Executive have launched an investigation, and relatives in Bulgaria have been informed.

Fellow members of the Oxford Stunt Factory, based in Canal Street, Jericho, were today mourning the death of their friend, known affectionately as 'Dino'.

OSF chairman Ding Boston said: "We don't quite know what to do. It's so distressing. He only joined this year. He was a very sweet, brave, intelligent guy and we are all dreadfully sad."

David Aitkenhead, who set up the activity at Woolavington a year ago, said he and his partner were "gutted" by the accident. They had no clues at this stage as to what went wrong.

The catapult, a replica of a medieval trebuchet, threw the student in a curving arc but he fell short of the safety net. It remains unclear why.

Mr Aitkenhead said: "I saw the accident, but it is impossible to say what happened. He missed the landing by falling short of the net. He didn't fly far enough and hit the ground."