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A search is underway for the body of a surfer who is believed to have been killed in a shark attack off the coast of a South Australian town.
Emergency services responded to reports of an attack off the coast of Granites Beach in Westall Way Loop near Streaky Bay about 10.20am today.
9News understands about six surfers were in the water but the 55-year-old man paddled out wider than the rest of the group.
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A witness on a clifftop said they saw the shark attack the man, which left him floating before he was attacked again.
The witness believes the shark was about 4.5 metres in length.
"Eyre and Western Police immediately responded and initiated a search with the assistance of Police Water Operations, PolAir, State Emergency Service (SES) and local volunteers," South Australia Police said in a statement.
"The man's body is yet to be found and the search will continue through to day's end," police said.
The beach is popular among surfers on the Eyre Peninsula.
It's also known for having a large population of great white sharks.
This is the third shark attack off the South Australian coast this year.
Streaky Bay is about 700 kilometres from Adelaide, on the state's far west coast.
