(CN) - A county worker in San Bernardino, California returned to a holiday party at a social services center Wednesday and sprayed the room with bullets from an assault rifle, killing 14 people and wounding 17 others, before he and his wife were killed in a wild shootout with police.
In a press conference late in the evening, Police Chief Jarrod Burguan said the main shooter was named Syed Rizwan Farook, 28, and confirmed that he was employed by San Bernardino as an environmental engineer in public health.
"We've obviously secured his office space," said the chief.
Farook was paired in the shooting with his wife, Tashfeen Malik, 27.
Farook was born in the United States, Burguan said. He could not confirm the background or ethnicity of Malik. He also said his investigators had not found a motive but he could not rule out terrorism.
The Farook name is of Arabic and Indian origin, and a Muslim association held a press conference late Wednesday where a family member offered sympathy and condolence to the victims of the shooting and their families.
The police chief said both Farook and Malik were armed with .223 caliber assault rifles, a DPMS model A-15 and a Smith & Wesson M&P 15, and both were also armed with semi-automatic pistols, one made by Llama and one by Smith & Wesson. All of those guns can be bought through the Internet.
Farook had attended a Christmas lunch gathering in the late morning and had an argument, said the police chief, returning within a half hour fully equipped with masks and body armor.
"There had to be some type of planning that went into this," Burguan said. "I don't think they just went home, put on these types of tactical clothing, grabbed guns and came back on a spur-of-the-moment thing."
Asked if Farook's supervisor had been killed, the police chief said that the couple had left what appeared to be a pipe bomb at the scene, which needed to be disabled. He said police had only just begun identifying the dead.
The late evening press conference followed a day of day filled with dramatic scenes starting around 11 a.m., with police cars racing past the courthouse in San Bernardino toward the social services center for disabled children where the shooting took place. They were followed by police cars from surrounding communities traveling at high speed up the I-210 freeway toward the desert city east of Los Angeles.
After a lengthy period of shooting at the social services center, Farook fled in a black SUV back to a residence in Redlands where he was tracked by the city's police force in the early afternoon. A car chase followed.
It ended in a chaotic gun battle, in which a policeman was injured and both Farook and Malik were killed. Afterward, an armored truck could be seen approaching a bullet-riddled SUV with an extended, armored, forward platform from which officers used a large hook to pull a woman's body from the cab.
Her companion's body was lying in the road next to the SUV, with his assault rifle nearby.
Speaking at the White House, President Barack Obama said: "We do not know yet what the motives of the gunmen are, but we do know there are steps we can take to make Americans safer."
As he has done after previous mass shootings, the president called for common-sense revisions to the nation's gun laws to "make these events rare."
It was the sixth mass shooting in the United States in the last week, and the 355th so far in 2015 involving four or more victims. It was also the deadliest mass shooting since Sandy Hook in December 2012.
At his press conference in San Bernardino, Burguan said: "We've seen this happen time and time again."
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