Couple's motive in California rampage a mystery for police, family

Authorities are still trying to determine why a man and a woman opened fire at a holiday party of his co-workers in Southern California, killing 14 people and wounding 17 in an attack that appeared to have been planned.

Syed Rizwan Farook, 28, and Tashfeen Malik, 27, who had a six-month-old daughter together, were killed in a shootout with police after Wednesday's bloodshed at the Inland Regional Center in the city of San Bernardino, a social services agency where Farook worked as an inspector.

San Bernardino Police Chief Jarrod Burguan said the motive remained unclear in the most recent U.S. mass shooting. He and David Bowdich, an assistant regional FBI director, both said it had not been determined if terrorism was a motive.

The guns used in the attack were legally purchased in the United States, the Associated Press reported, citing a spokeswoman for the U.S. Bureau of Alcohol, Tobacco, Firearms and Explosives.

Farook was U.S. born, while Malik's nationality was yet to be determined.

Farook's family and co-workers struggled to make sense of the shooting, the deadliest in the United States in three years. His brother-in-law went before television cameras and said he had...