Another shooting in US claims lives of 3 police officers

A day after a Vietnamese-American shot dead 14 people before claiming his own life in Binghamton in US, another gunman killed three police officers responding to a call of domestic disturbance and turned a quiet Pittsburgh street into a battlefield for over four hours.

Though the incidents occurred in towns more than 400 kilometres apart, there were similarities as both gunmen had lost their jobs in the economic recession and were feeling frustrated, media reports suggested.

The shootings led to fresh calls for toughening the laws for gun possession as analysts expressed fears that such incidents could increase if the economic difficulties continue.

Both assailants were wearing bullet proof vests which showed that they were prepared to fight the police.

The gunman in Pittsburgh, identified as 23-year old Richard Poplawski, was apparently lying in wait for the police after his mother sought help.

He killed two police officers at the door and then third who came to help of his colleagues yesterday. Two other police officers were injured.

Then followed a four-hour standoff during which the police officers fired more than 100 rounds but Poplawski was not seriously hurt apparently because of the bullet proof vest. He was shot in the leg and has been charged with three counts of homicide and aggravated assault.

In both cases, officials have not been able to establish the motive but Poplawski's friends were quoted as saying that he was upset over losing his job recently and also feared that the Obama administration might ban guns.

Police have also not been able to establish a clear motive in the case of Binghamton killer Jiverly Wong as his computer hard drives gave no help. But he was said to be upset over people making fun of his poor English and was a loner. He too had lost his job and was unable to get another.

Law enforcement officials said that he apparently came to fight the police but killed himself when he heard sirens of police cars.