A 67-year-old man was robbed in a parking lot at Graton Resort and Casino in Rohnert Park Tuesday morning, according to the Sonoma County Sheriff's Department.
The robbery was reported at about 6:30 a.m., when the victim was struck in the head with an unknown object and robbed outside the casino, according to the sheriff's office.
The victim said he was robbed by two suspects, who stole an undisclosed amount of cash and personal property, the sheriff's office said.
The victim was taken to Memorial Hospital to be treated for severe head trauma, the sheriff's office said.
The incident remains under investigation by the sheriff's department and Graton Casino security personnel.