The US economic crisis and soaring job losses have brought a rash of killings across America with at least 58 fatalities in eight incidents over the past month.

A Vietnamese immigrant who had recently been sacked from his job at a vacuum cleaner factory stormed into an immigration centre in New York State last week and killed 13 people before turning the gun on himself. A letter sent by the gunman to a local television station blamed his “poor life” and police harassment for the rampage.

In Oakland, California, a 26-year-old man on parole shot and killed four police officers after a routine traffic check on March 21. His relatives said that he was frustrated about not finding work and feared returning to jail.

Two weeks later, in Pittsburgh, Pennsylvania, an unemployed man opened fire, killing three police officers.

In January a man in Los Angeles sent a letter to a local television station filled with tales of job loss, mounting debt and bad cheques. He was found dead, having shot his wife and five children before killing himself. It was the fifth such incident in the Los Angeles area in a year.

While detailed statistics on such tragedies have begun to be kept only in recent years, experts note an emerging pattern. Kristen Rand, legislative director for the Washington-based Violence Policy Centre, said that in most so-called murder-suicides, particularly in the “family annihilator scenarios”, there was “clear, significant involvement of financial pressure”.

“And there has clearly been an increase since the economic down-turn,” she added.

Mark Safarik, a former FBI profiler, is also startled at the number of deaths. “Boy, this is a lot,” he said. He noted that most people who commited such crimes shared the presence of a single catastrophic event, or trigger. “It’s the . . . perfect storm of someone’s last shot at something. For them there’s just no other way out. Or if there’s another way out, they don’t choose it, because they’re going to punish somebody,” Mr Safarik said.

He added: “I think that people that are on the edge, that are contemplating such tragic events, sometimes all it takes is that being highlighted in the media for them to go, ‘You know, I could do something like that. I’m that angry’.”

The recent spate of shootings has also reignited the emotive US debate over gun control. In 2005, the most recent year for which official records exist, there were 11,346 gun-related killings in the United States. In England and Wales there were 50 homicides involving firearms during the reporting period from 2005-06.

Gun-control advocates hope that a new Democratic Administration will mean an opportunity to tighten restriction on firearms but others fear losing their weapons. The shooter who murdered three police officers in Pittsburgh, friends said, feared that the Obama Administration would take away his guns.

Paul Helmke, president of the Brady Campaign to Prevent Gun Violence, said: “We have a gun crisis in America. As important as the economic crisis is, the right to be safe at home and work and play needs at least as much attention from our policymakers as the right to economic security.” Calling for tougher gun laws, he added: “What we’re doing now is not working.”

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