Sources: Data from San Bernardino phone has helped in probe

Hacking the San Bernardino (CA) terrorist's iPhone has produced data the FBI didn't have before and has helped the investigators answer some remaining questions in the ongoing probe, US law enforcement officials say. Apple and the FBI are squaring off again April 19 in testimony at a House hearing on encryption, with the recent battle over unlocking a terrorist's phone looming in the background. Investigators are now more confident that terrorist Syed Farook didn't make contact with another plotter during an 18-minute gap that the FBI said was missing from their time line of the attackers' whereabouts after the mass shooting, the officials said.

The phone has helped investigators address lingering concern that the two may have help, perhaps from friends and family, the officials said. The phone didn't contain evidence of contacts with other ISIS supporters or the use of encrypted communications during the period the FBI was concerned about. The FBI views that information as valuable to the probe, possibilities it couldn't discount without getting into the phone, the officials said. Private sector hackers hired by the FBI helped investigators gain access to the phone, which was at the center of a legal dispute between the government and Apple.