A 27-year-old man was jailed for nine years yesterday for shooting a fellow clubber with a tiny key fob gun that police have warned is highly dangerous.

Detectives believe around a hundred of the four-inch Bulgarian-made weapons, which fit easily in the palm of the hand, are currently in circulation.

They are now trying to recover the firearms, which they believe pose more of a threat than normal guns as they can be easily concealed.

Yaw Darko-Kwakye was lucky to survive being shot from close range in December last year - the first known example of the weapon being used.

Marcus Henry, 27, pulled the gun from his trouser pocket and fired two shots, one of which hit Mr Darko-Kwakye in the right shoulder, after a row over the victim's girlfriend in the Departures nightclub in central London.

Henry, of Cedars Road, Clapham, south London, was found guilty by an Old Bailey jury of unlawful wounding and two firearms charges.

Judge Christopher Moss told him the offence of bringing a loaded firearm into a public place and using it should meet with a "severe prison sentence".

Mark Heywood, prosecuting, asked for the key fob gun to be forfeited but not destroyed, so the "novel weapon" could be used for training purposes.

Outside court, Detective Sergeant Dave Carter, of the City of London police, said a consignment of the weapons was brought into the country a few years ago.

Designed to be used as flare guns, they have been converted to use 0.25-inch live rounds, Carter said. "It is not particularly accurate, but from a short distance it can be fatal."

He said neither City police nor officers from the Met's Trident unit had come across examples of the weapons being used before. "They are very dangerous, because they look like something else and can be concealed very easily. They are arguably more dangerous than an average handgun.

"We are very keen to try and locate as many of them as we can and take them off the streets as quickly as possible."

The guns are cocked by pulling part of the key ring and have buttons on the side to fire them and to open them for reloading.

The gun used by Henry was found hidden in a sock with traces of his blood on it during a police search of a house.

Henry's victim only survived because, due to the short barrel of the weapon, the bullet did not fire straight, rotated through the air and hit him side on.