LOS ANGELES (AFP) - A man dressed in a Santa Claus costume burst into a Christmas Eve party at his former in-laws and opened fire, killing at least eight people before taking his own life, US officials said Friday. Bruce Pardo, 45, who reportedly had been embroiled in a bitter divorce with his ex-wife, knocked on the door of her parents' home in the quiet Los Angeles suburb of Covina and launched the assault just before midnight, police lieutenant Pat Buchanan said. An eight-year-old girl who answered the door was shot in the face before Pardo stormed the home in Covina, 23 miles (37 kilometres) east of Los Angeles, and began spraying revellers with bullets fired from a semi-automatic handgun. After partygoers fled the scene, Pardo torched the house with a bizarre home-made incendiary device before making his getaway. Pardo's body was found with self-inflicted gunshot wounds early Thursday, a few hours after the rampage, police said. He had been killed by a single shot to the head at his brother's home in Sylmar, approximately 25 miles away. Later Thursday, a rented car parked outside the property was discovered to be loaded with 300 rounds of ammunition and a pipe bomb. The car burst into flames as bomb disposal experts moved in, reports said. Police had received a series of emergency calls alerting them to the initial incident, and when they arrived, the house was engulfed in flames and guests were running out, Buchanan said. Neighbours reported hearing a loud explosion before the blaze erupted. Two girls, including the eight-year-old who answered the door, were hospitalised with gunshot wounds and a 13-year-old girl was treated for injuries that were not life threatening. Around 80 firefighters were deployed to tackle the fire that destroyed the house. Three bodies were found in a basement, Buchanan said, with the death toll rising to eight as investigators from Los Angeles County Coroner's Office picked through the crime scene during the day. Several of the victims were reported to be burnt beyond recognition. No formal identifications have been released although Pardo's former in-laws were reported to be among the dead. Buchanan told CBS2 television the shooting was "extremely unusual and very shocking." "It's just not something we see here at any time of the year " especially during Christmas," he said. Police were searching Pardo's home Thursday for clues to his bloody rampage. Local media said the gunman had been involved in an acrimonious divorce with his ex-wife. "Maybe there's some (sign of) planning, maybe letters or anything that will give us more clues about the state of his mind," Detective Antonio Zavala was quoted as saying by the Los Angeles Times. Grief-stricken friends of the victims described Pardo as a "coward." "To know that one individual, one coward, could bring so much devastation and heartache to a family," said family friend Rosa Ordaz. "For him to come and do this on such a special night and to destroy this whole family." Acquaintances of Pardo meanwhile were stunned by the former aerospace engineer's killing spree, according to the Times. "This is shocking," said Jan Detanna, the head usher of Pardo's church. "He was the nicest guy you could imagine. Always a pleasure to talk to, always a big smile."