Two gamekeepers have been accused of the manslaughter of an 18-year-old colleague after a shotgun went off in a 4x4 vehicle.

Caernarfon crown court heard the tragedy happened after a night out in February last year, in a pub car park at the village of Llanbedrog, near Pwllheli.

Opening the case to a jury, prosecuting QC Patrick Harrington said: "Just after midnight on February 5 Peter Colwell was shot dead as he sat in the middle back seat of a Land Rover Discovery. The weapon that killed him was a semi-automatic shotgun and was discharged by Ben Fitzsimons. He had been sitting in the front passenger seat of the vehicle with the gun propped up to his right with the muzzle facing backwards.

“The gun was owned by Ben Wilson. He wasn’t in the car at the time. He was in the car park.”

Mr Harrington said: "The killing was neither deliberate nor malicious. But a young man died as the result of the cavalier disregard of the fundamental rules of gun safety by Ben Wilson and Ben Fitzsimons. The muzzle shouldn’t have been pointing at the teenager, and there had been drinking by Fitzsimons and a gun which could be a “lethal mix.”

The prosecution claimed “gross negligence”.

The QC said Wilson had pleaded guilty to unlawfully having a loaded shotgun in a public place.

Mr Harrington said Ben Fitzsimons, Wilson, Harry Butler and Peter Colwell were all gamekeepers on the large Boduan Estate near Pwllheli. Wilson lived at the time close to his employer who had a state-of-the-art gun store.

The prosecutor said it would have been simple for Wilson to store the gun there

Ben Fitzsimons, aged 23, of Nanhoron, Pwllheli, and Wilson, 29, now of Ely, Cambridge, deny manslaughter.

Fitzsimons and his brother Michael Fitzsimons, 25, also of Nanhoron, and Butler, 23, of Llaniestyn, Pwllheli, deny unlawfully having a loaded shotgun in a public place.

CCTV footage showed a flash as the gun went off. Mr Harrington said the weapon had a safety catch which, when operational, stopped it being fired and pressure had to be applied on the trigger, too.

The trial continues before Mr Justice Picken who said the case was likely to go into a third week.