The helicopter stopped following the suspected stolen car and instead tracked the drone to a house in Martinez, where local police talked to the drone's owner and his host family, Andrews said.
Andrews said the CHP is still compiling its report and hasn't decided whether to forward it to prosecutors for possible criminal charges. Andrews said this is the first time a drone has interfered with a CHP aircraft in Northern California.
The Federal Aviation Administration said it will investigate the incident as well. The FAA said drones are a growing safety concern, and that it expects more of the pilotless aircraft to fill the skies. The Consumer Electronics Association predicts hundreds of thousands of drones will be sold this holiday season.
The FAA could take a number of steps, from warning the operator to administering a fine.
"The FAA is very concerned with the increasing number of reports we're getting from pilots about small drones flying near their aircraft -- some of them thousands of feet up or in busy arrival and departure corridors," FAA spokesman Ian Gregor said.
The FAA now receives about 100 reports a month from pilots who say they've seen drones flying near planes and airports, compared with only a few sightings per month last year. So far there have been no accidents, but agency officials have said they're concerned that a drone weighing only a few pounds might cause serious damage if it is sucked into an engine or smashes into an airliner's windshield.
Pilot sightings of drones have doubled since last year, including near manned airplanes and at major sporting events, Transportation Secretary Anthony Foxx said at a news conference in Washington in October.