U.S. authorities look for militant links to shooters

The couple suspected of killing 14 people at a holiday party in California amassed thousands of rounds of ammunition and a dozen pipe bombs, authorities said on Thursday as they sought clues to the pair's motives and whether they had links to Islamist militants.

Syed Rizwan Farook, 28, and his wife, Tashfeen Malik, 27, were killed in a shootout with police five hours after Wednesday's massacre at the Inland Regional Center social services agency in the city of San Bernardino, about 60 miles (100 km) east of Los Angeles.

Twenty-one people were wounded in the attack, which ranks as the deadliest instance of U.S. gun violence since the December 2012 shooting at Sandy Hook Elementary School in Newtown, Connecticut, in which 27 people were killed.

The dead and wounded from Wednesday's bloodshed accounted for nearly half of the estimated 75 to 80 people who were in the room where the armed couple opened fire.

San Bernardino Police Chief Jarrod Burguan told a news conference the search of a townhouse leased by the two shooting suspects in the nearby community of Redlands turned up flash drives, computers and cell phones.

Officials in Washington familiar with the investigation said there was no hard evidence of a direct connection between the couple and any militant group abroad, but the electronics would be checked to see if the suspects had been browsing on jihadist websites or social media.

One U.S. government source told Reuters the FBI was examining information indicating that Farook was in contact with individuals who had themselves been under FBI investigation, some from cases already closed. The source also said it was possible that one or more of the Farook contacts under scrutiny were overseas.

But no information has emerged suggesting any ties or contacts between Farook and the Islamic State or other specific militant groups, the source said.