The San Benito Police Department has issued a Silver Alert for a missing 86-year-old man.

Juan Chavez Carrillo is diagnosed with Alzheimer's and was last seen Tuesday morning at the 1100 block of North Shore Drive on his purple bicycle heading towards an unknown location, according to a news release.

Police believed Carrillo "is considered to be a risk to himself if left alone", according to the release.

Carrillo is described as a white male, 5'7, thin build weighing approximately 125 to 145 pounds with gray hair, brown eyes and was wearing a long sleeve shirt, tennis shoes and black veteran's baseball cap.

Anyone with any information on his whereabouts is urged to call the San Benito Police Department at (956) 361-3880.