Santa Clara police are asking for the public's assistance in locating a suspect in an "unprovoked and ruthless" attack on a 91-year-old man visiting his late wife's grave site.

The incident was reported 10:42 a.m. on Saturday, Sept. 14, at the Mission City Memorial Park cemetery. Police said a male suspect struck the elderly man on the head from behind with a large rock before he stole property from him and took off on a bike.

Responding officers searched the area but were unable to locate the suspect. The suspect is described as a man between 35 to 50 years old, standing 5 foot 9 inches to 6 feet tall, with a medium build. Police said the suspect also has slicked back hair, a grey moustache and was wearing a white T-shirt with long black shorts. He was last seen riding a grey and black mountain bike.

The victim was transported to a hospital.

Police said the attack appears to be an isolated one. Anyone with information is asked to contact Detective Sgt. Nick Richards at 408-615-4814 or anonymously at 408-615-4TIP (4847).