six police officers have been threatened by a sniper in pittsburgh - the second mass shooting in the nation in 24 hour . the officers were responding to an anonymous dispatch from the office of the gunman , named as richard poplawski , 23 . police reported he was waits , armed with guns and a wearing uniform . he murdered two officers as they entered the house , and a third member tried to help them . he then traded gunfire with police for four minutes before being defeated and giving himself up . his friends claim he had earlier lost his badge , and was fearful that us president barack administration was about to ban bullets .
In Pittsburgh the police killed a gunman.