Pious California killer showed no outward signs of violence

(AP) — With a young wife, infant daughter and government job, Syed Farook appeared to have arrived at a sweet-spot in life.

The FBI was investigating the shootings as a potential act of terrorism but reached no firm conclusions Thursday, said a U.S. official briefed on the probe.

Separately, a U.S. intelligence official said Farook had been in contact with known Islamic extremists on social media.

[...] law enforcement officials from local police to Attorney General Loretta Lynch cautioned it could have been work-related rage.

Farook had no criminal record and was not under scrutiny by local or federal law enforcement before the attacks.

Police said they also had 12 pipe bombs, tools to make more explosives, and more than 3,000 rounds of ammunition at home.

Police Lt. Mike Madden, one of the first officers to reach the room at the social services center, where Farook's colleagues from San Bernardino County's public health department had gathered, said the carnage was "unspeakable," the scene overwhelming: the smell of gunpowder, the wails of the injured, the blood, fire sprinklers pumping and fire alarms blaring.

Patrick Baccari, who sat at the same table as Farook at the employee party, recalled he was short on words and inclined to talk about cars, not religion.

A profile on a matchmaking website for South Asians that matched Farook's name, California hometown, county health job and Muslim faith said his interests included target shooting in his backyard.

Farook's mother alleged in 2006 that her husband, also named Syed, attacked her while her children were present, dropped a TV on her and pushed her toward a car, according to records.