A U.S. judge on Tuesday ordered Apple Inc to help the FBI break into a phone belonging to one of the shooters in the December attack in San Bernardino, California, the latest episode in a long-running dispute between tech companies and law enforcement over encryption.

Apple must provide "reasonable technical assistance" to investigators seeking to unlock the data on Syed Rizwan Farook's iPhone 5C, U.S. Magistrate Judge Sheri Pym of U.S. District Court in Los Angeles ruled.

This includes disabling its auto-erase function, which activates after 10 consecutive unsuccessful pass code attempts, and allowing investigators to submit pass code guesses via electronic means.