A missing surfer is believed to have been killed in a shark attack at a popular South Australian surf spot as a police search continues.

The 46-year-old Elliston man was surfing when he was attacked by the shark, and the incident was witnessed by multiple surfers at Walkers Rock Beach, roughly 365 kilometres west of Adelaide, police said.

Police, SES and local community members have been searching for the man after the incident was reported shortly after 10am on Saturday.

Superintendent Paul Bahr thanked the local community and emergency services for their assistance with the search. 

“It’s not easy when it’s a local involved but we commend their strength and their want to assist,” he said in a statement on Saturday evening.

“We will continue to search with the assistance of local emergency services and other resources.”

No one else was injured in the attack.

The incident occurred near a reef break popular with surfers in an area with a history of shark attacks.

The last suspected fatal shark attack in South Australia occurred in 2021, when a Victorian man disappeared while snorkelling in waters near Port Macdonnell, close to the Victorian border.

A damaged wetsuit was later found and a shark was sighted in the area by a police helicopter.

By Adrian Black in Wodonga