A former Army sergeant who made guns for gangs operating in Liverpool, Manchester and Birmingham was facing a long jail term last night.

Detectives said Paul Alexander, 53, was a "significant" supplier and had been tracked down following the launch of an operation against gangs in the wake of the shooting of 11-year-old Rhys Jones in Liverpool two years ago.

Police said they found a "gun factory" at a house Mr Alexander rented in Bardfield Saling, Essex - and his weapons and ammunition had been linked to 28 firearms crimes in the UK.

Investigators said Mr Alexander used 30 aliases and ferried guns and ammunition to the Midlands and the North West in hire cars.

Chelmsford Crown Court was told yesterday that Mr Alexander had admitted possessing firearms and ammunition with intent to endanger life, converting imitation firearms into real firearms, buying and selling prohibited ammunition and money laundering.

He is due to be sentenced in November.

Police said Mr Alexander was born Paul Daintry in Bury, Lancashire and had lived in Stoke-on-Trent and Bath as well as regularly travelling abroad.

Detectives suspect he made hundreds of thousands of pounds and an investigation aimed at locating and seizing assets is under way.

Mr Alexander was arrested in September 2008 after a 12-month operation involving detectives from Merseyside, Essex and investigators from the Serious Organised Crime Agency (Soca).

"The guns and ammunition supplied by Paul Alexander are being linked to numerous shootings," said Mick Layton, deputy director of Soca.

"Put simply, he was dealing in death."

Investigators said they hoped Mr Alexander's arrest had dealt a significant blow to gangs operating in the Midlands and the North West.

Rhys was killed as he walked home from football training in Croxteth Park, Liverpool, in August 2007.

Gang member Sean Mercer, 18, fired three shots from a 1915 Smith & Wesson revolver across a pub car park at opposition gang members - the second bullet hit the boy. Mr Mercer was given a 22-year jail term after being convicted of murder. Detectives said there was no evidence to suggest the gun used in the shooting had been supplied by Mr Alexander.