A piece of a wetsuit has been found during the search for a missing man who is believed to be dead after a shark attack.
Teacher Simon Baccanello went for a morning surf on Saturday at Walkers Rock Beach, in South Australia, but never returned.
Police have now been searching for three days and believe he was killed.
A 22-year-old witness, Jaiden Miller, told the Adelaide Advertiser he saw the shark "thrashing around" during the suspected attack.
He continued: "The shark obviously has let go and come back and got him for a third time."
While Simon's body remains missing, his surfboard was recovered with "one bite in the middle", emergency services manager Trevlyn Smith said.
The Elliston Area School teacher was at the back of a group of about a dozen surfers when he was attacked. No one else was injured.
Superintendent Paul Bahr, from SA Police's Eyre and Western Local Service Area, said many of the surfers who were in the water at the time are going "to be very, very distressed" as it was "quite a horrendous incident".
Few details have been released and police say the search will continue until the end of the day before they reassess the situation.
Elliston School principal, Chad Fleming, said Mr Baccanello was "absolutely adored by students and staff".
Elliston is an isolated coastal town about 370 miles west of Adelaide with a population of less than 400.
He continued: "In our short time at our school, and in our community (and in schools around the world), he had a sincerely positive impact on us all.
"With his dedication to education and an enthusiastic and positive approach to learning and life, Simon showed care and respect to everyone.
"He was an avid surfer and absolutely loved living the Elliston lifestyle, being a keen fisherman too.
"He was also involved in junior sports, football, and tennis."
Mr Fleming said the community would "wrap our arms around each other" to deal with the circumstances "as best we can".
"It's going to take a while for our community to recover," he said.
On Sunday, State Emergency Services unit manager Trevlyn Smith said Mr Baccanello was "well-known" in the local community.
Superintendent Bahr said it was a "very tragic day" for the "tight-knit" community, and said the family were provided with an update late on Saturday night.
This would mark the first fatal shark attack off the coast of South Australia since 2014 when another teacher was killed in the waters.
