An FBI dive team reportedly pulled an object from a San Bernardino lake Friday, seeking evidence pinpointing the motive and history of the attackers who killed more than a dozen people during a holiday party.

One diver handed the unknown item to an official wearing gloves, who put the object in a plastic bag, the Press-Enterprise reports.

Investigators are looking for a hard drive that may have been dumped in the lake, a law enforcement official briefed on the investigation told The Associated Press. David Bowdich, chief of the FBI's Los Angeles office, said investigative leads indicated the shooters had been in the area the day of the massacre and said the search of the lake could take days.

Fox News has learned that in 2012, one of the gunmen, Syed Farook, conspired with former neighbor Enrique Marquez, the man who purchased the rifles used in the deadly attack in San Bernardino on Dec. 2. The plot would have targeted the Los Angeles area.

It appeared the two were scared off the idea by the November 2012 arrests of four Southern California men attempting to travel to Afghanistan to wage holy war.

The small, urban lake is about 3 miles north of the shooting site.

Authorities say Farook and his wife, Tashfeen Malik, opened fire on his fellow San Bernardino County health inspectors during a holiday party, killing 14 people and wounding 22 others. The couple died hours later in a police shootout, leaving behind a 6-month-old daughter.

FBI Director James Comey has said Farook had been in communication with individuals who were being scrutinized by the FBI in terrorism investigations, but that the contact he had was not enough to bring him onto the law enforcement radar.

The FBI has interviewed hundreds of people and conducted searches looking for evidence. Bowdich says it's possible the agency will do neighborhood canvasses in the future, too.

Fox News' Adam Housley and The Associated Press contributed to this report.