Gun owners are being offered a legal way to side-step the new anti-firearms laws and keep their favourite weapons - provoking outrage from Dunblane campaigners.
A company is offering to deactivate firearms for pounds 35 and beat the government ban.
Gill Marshall-Andrews, chairwoman of the Gun Control Network, set up after the Dunblane massacre, said: "Deactivated weapons can induce fear in just the same way as a working gun."
Anti-firearm groups are angry that a company called Worldwide Arms has placed a number of full-page advertisements, including one in this month's Gun Mart magazine, offering to deactivate guns. It says: "The Government has banned it. Do you want to keep yours? Then let us deactivate it." It adds: "They are legal and licence free."
Police chiefs have expressed growing concern about the rise in the number of deactivated weapons and argue many are being reactivated and used by criminals in a thriving black market.
A deactivated gun must have a number of alterations carried out, including the removal of the firing pin. It is then checked by government inspectors. But Roy Penrose, the national co-ordinator of the Regional Crime Squad, said: "There's only one place to deactivate [the guns], and that's in the smelter."
Sir Paul Condon, the Metropolitan Police Commissioner, also expressed concern about the growing trade in "deactivated" firearms from Eastern Europe. The guns, including Uzi machine guns and Kalashnikov assault rifles, are imported as ornaments and reactivated by gunsmiths and criminals in Britain.
Under the Firearms Bill that comes into force later this year, all guns above .22 calibre must be either destroyed, sold abroad or deactivated.
An employee at Worldwide Arms, based in Stafford, said strict procedures are followed to deactivate guns. But he refused to comment on complaints that they could still be dangerous.
A Home Office spokesman said that the regulations on deactivation had been tightened up before the Dunblane killings and were now "considerable".
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