Albuquerque ? A sheriff’s department helicopter that crashed behind a home in Albuquerque during the weekend was brought down by gunfire, authorities said Tuesday.

Bernalillo County Sheriff Darren White said authorities have no suspects yet but are working with the FBI.

Investigators examining the wreckage Monday noticed what appeared to be a small hole in the windshield of the cockpit, White said. “Deputies also located several items that are consistent with a bullet that has fragmented upon impact.”

Both the civilian pilot and the deputy on board when the helicopter crashed early Saturday survived with minor injuries.

White said the pilot and deputy were assisting deputies on the ground who were investigating a burglary call when the helicopter lost power. The pilot told White he heard a pop, then felt the helicopter pitch and shut down.

The helicopter landed about 15 feet from the back of a house