An Israeli company is reportedly helping the FBI to hack the phone of a terrorist who carried out a mass shooting in California last year.

Terrorist couple Syed Rizwan Farook and Tashfeen Malik killed 14 and injured 22 in the attack on a San Bernardino County Department of Public Health training event and holiday party in December.

The FBI was engaged in a legal battle with Apple to get the technology company to unlock the mobile used by one of the shooters, but proceedings were suspended after US prosecutors revealed on Monday that a “third party” had offered assistance.

According to the Yedioth Ahronoth newspaper, Israeli mobile forensics software firm Cellebrite is the third party.

A spokesman for Cellebrite confirmed that the company “works with the FBI in general”, but said he was not able to comment on this case.