The 45-year-old man committed suicide around 3:30 a.m. on Christmas at his home in Sylmar, a suburb about 50 kilometers north of downtown Los Angeles, after his shooting spree at the Christmas Eve gathering.

Bruce Jeffery Pardo was in a Santa Claus suit when he showed up at the Christmas party and began shooting, before torching the house in Covina of east Los Angeles, according to police spokesman Pat Buchanan.

Police did not release information about the three people killed at the party, but said that an 8-year-old girl and a woman in her 20s wounded in the attack are expected to survive.

Pardo, who was reportedly estranged from his wife and in a messy divorce, used cocktails to set the house on fire, according to local television reports.

Describing the incident as "extremely unusual and very shocking," Buchanan said that the killings were just not something people saw at any time of the year, especially during Christmas.

About 80 firefighters arrived at the scene soon after the fire was reported, but were held at bay as the house burned and police tried to make sure it was safe. The house was completely destroyed by the fire, which later was put out by firefighters.

Police said they have no information about who were at the party and whether they were related to the killer.