Mr. Jin is wanted on a separate warrant for the March 9 murder of a woman, described as his girlfriend, in southwestern Yunnan Province.
Johnson said they immediately summoned tactical and support personnel who obtained a separate warrant charging Gaines with assaulting a police officer.
Currently, investigators must get a separate warrant for each network service provider whose system the signal crosses, which can be hundreds in a single instance.
For that, law-enforcement agents need a separate warrant: one far harder to obtain because it requires suspicion of particular individuals and proof that "normal investigative procedures have been tried and failed".
After applying for a separate warrant for Mr. Ouazzani's communications, they identified two additional conspirators and discovered they were "in the very initial stages" of the stock exchange bomb plot, he said.
Both sides agree that Apple has given significant technical assistance with the San Bernardino case already; in response to a separate warrant, it gave the F.B.I. the iCloud back-ups for Farook's phone (the most recent was from some weeks before the shooting).
A separate warrant for Mr Whyte's arrest was issued in Scotland last week over a separate case.
"This rule change would permit agents to go to one federal judge, rather than submit separate warrant applications to each of the 94 federal districts.
A week later, police obtained a separate warrant to search David's car.
Defense attorneys argued that, because the tape was not in plain sight, investigators had overstepped their bounds and should have obtained a separate warrant to watch it.
