Sources: Data from San Bernardino phone has helped in probe

Hacking the San Bernardino 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, U.S. law enforcement officials say.

Apple and the FBI are squaring off again Tuesday 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.

'No evidence' of ISIS contact

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.

Apple was fighting a judge's order to help the FBI get past security features to get access to the phone's data.

One of the points of contention during the legal fight was Apple's argument that the FBI already had obtained relevant data from the iCloud account linked to the phone and from other data not stored on the device, that breaking into the device would be of little use.

The government contended investigators couldn't be sure until they accessed data from the phone.

FBI investigators now have concluded there was data on the phone they didn't have previously, law enforcement officials said, declining to offer more specifics.

The data is still being analyzed and more leads are being followed, the officials said.

Much of the mystery of the missing 18 minutes, and why the terrorists drove seemingly aimlessly around the San Bernardino area following the attack, remains unsolved.

CNN