Roy Penrose, the director-general of the National Crime Squad (NCS), believes gun-toting characters played by stars such as Bruce Willis, Arnold Schwarzenegger and Sylvester Stallone have encouraged criminals and society in general to become blase about killing. He said the use of hit-men was a "growing issue" nationally.
He also said that the Government's handgun ban, provoked by the Dunblane massacre, had no effect on the supply of firearms to criminals in the UK. Automatic weapons were being smuggled in and were still freely available.
Mr Penrose became the first director-general of the NCS, which has 1,450 officers, when it was set up in April to combat serious and organised crime nationally and internationally.
He says screen violence and firepower has led to a desensitisation of people towards guns and shootings. "I'm conscious of seeing the Death Wish [films], Sylvester Stallone, Arnold Schwarzenegger and Bruce Willis - those sort of big macho-type people - shooting bloody great guns," he said. "I believe that society has become more tolerant of violence and has some appetite for violence."
He argued the combined effects of drugs, money and the glorification of guns and violence meant that if someone said" "`Here's pounds 10,000. Go and blow that geezer away,' they just do it - life appears to be cheap."
Police are notoriously reluctant to discuss contract killing, but Scotland Yard sources admit that "hits" have risen steadily in the past five years. Detectives from the Yard's Organised Crime Group estimate there are up to 20 hit-men operating in London alone, with prices ranging from pounds 1,000 to pounds 20,000 depending on the target.
Most contract killings are between rival crime gangs, increasingly in disputes over drug deals. However, a number have involved businessmen disposing of rivals or partners, and even husbands and wives getting rid of an unwanted spouse.
Last month a financial adviser to one of London's most powerful underworld gangs was shot dead on his doorstep by a hit man. Solly Nahome, 48, a diamond dealer, was killed as he returned to his family home in Finchley, north-west London.
In September, Peter Morris, 52, a civil engineer from Wolverhampton, was jailed after admitting soliciting the death of his wife. He paid an undercover policeman a pounds 500 downpayment for the "hit" after a neighbour with whom he had shared his plans went to the police.