Sierra, who was visibly shaken, said she thought it was an airsoft gun and kept walking. She said seconds later, she felt something buzz by her head and quickly realized they were bullets. Three or four of them.

Sierra said she ran into a nearby home filled with strangers and explained what happened. She looked down and saw her iPhone had been shattered.

Brown said the scope of the investigation has allied agencies working together, including UC Police, the California Highway Patrol, Santa Barbara Police, investigators with the District Attorney's Office, California State Parks law enforcement and criminalists with the Department of Justice crime lab.

The sheriff is asking for the public's help with the investigation and offered the Santa Barbara County Sheriff's Office Tipline to anyone with information: 805-681-4171.