UPDATE: Was It an Accident or Was It Murder?

See a more recent story at http://patch.com/A-g8Q7

First police thought it was a tragic accident at the end of a St. Patrick's Day party, but now they were calling it a homicide.

Brian Russell Kaplon, 32, an NBC Universal digital distribution executive who grew up in Chatsworth, was shot in the chest early on March 18 with a semi-automatic AR-15 rifle, a civilian version of the U.S. military's M16. Most fire .223-caliber bullets.

Kaplon was shot in the garage of childhood friend David Andrew Armstrong, 32, in the gated community of Sorrento in Porter Ranch. He reportedly was rushed to a hospital, where he was pronounced dead.

By Wednesday, Kaplon's father, Joe, was told by police that his son's death wasn't what it seemed, the Los Angeles Times reported. Lt. Fred Corral of the Los Angeles County coroner’s office told the Times that Kaplon's death was determined to be a homicide.

Police officials have not explained why they changed their view of the case from an accident to a homicide other than to say the decision followed a review of the physical evidence. Court papers say Armstrong "personally and intentionally discharged a firearm ... which caused great bodily injury and death to Brian Kaplon."

Armstrong was charged with murder Thursday and was released after first raising $1 million bail and then raising a second $1 million, the Los Angeles County district attorney's office told the Times.

James Blatt, a lawyer for Armstrong, quoted in the Times, continued to maintain the shooting was "a tragic accident" for which Armstrong had no motive. If convicted on all charges, Armstrong faces a sentence of 25 years to life in prison.

Blatt told the Times that the two men had been friends since fifth grade and that their families were also close.

Joe Kaplon said Armstrong kept several guns and rifles in the house on the 20000 block of Vercelli Way. “Because of one of those guns I had to bury my son yesterday,” he told the Times.

It was unclear if Armstrong had a permit for the weapon, which is considered an assault rifle under California law.

The father of 2-year-old daughter Chloe Ilene, Brian Russell Kaplon and his wife, Kristi Danielle, were expecting twins in May. They made their home in the Promenade subdivision of Porter Ranch.

The Chatsworth High School graduate received a BA in business economics from UC Santa Barbara and earned his MBA degree at USC. He had previously worked for several years as an accountant at Ernst & Young.

Armstrong is due to appear in court April 12.

The 2000 assault weapons ban in California increased interest in the AR-15. At least a half-million of them are believed to be in civilian hands statewide.

An earlier version of this story appears at patch.com/A-ggYH.

City News Service contributed to this report.