The California Highway Patrol activated a Silver Alert Saturday to help the Los Angeles Police Department locate an at-risk 75-year-old man who went missing from the Mid-Wilshire area of Los Angeles.

William Buchanan was last seen at about 3 a.m. Saturday around South Victoria Avenue and West Olympic Boulevard, according to the CHP. He was believed to be on foot.

Buchanan suffers from dementia and Alzheimer’s disease, the Los Angeles Police Department reported.

He is Black, 5-feet-8 inches tall, 170 pounds, with gray hair and brown eyes, and was wearing a black hat, a black shirt with graffiti, blue jeans and black shoes.

Anyone who sees Buchanan was urged to call 911 or the LAPD Wilshire Division at 213-473-0476.

The CHP activates a Silver Alert when an elderly or developmentally or cognitively impaired person goes missing and is determined to be at risk to provide immediate information to the public and aid in their swift recovery.