Was a great white shark involved in the disappearance of snorkeler?

A 29-year-old man who was snorkeling for lobsters in Anna Bay, Australia, went missing Sunday afternoon, and after a two-day search, authorities have failed to locate him.

Scott McGuire was initially snorkeling with a friend off Birubi Point in Port Stephens before the friend returned home, according to the Sydney Morning Herald. When McGuire failed to return to shore, family members called police.

Divers searched the waters from Birubi Point to Boat Harbor on Monday without finding a trace of the snorkeler. A search on Tuesday, which included a police helicopter, proved futile as well, the Port Stephens Examiner reported.

The area McGuire was snorkeling in is known as being "notoriously sharky waters," according to Seven News.

Several shark attacks have occurred in the past decade in waters off Port Stephens, a known nursery for great white sharks. A 31-year-old surfer was bitten on his foot by a shark at Birbubi Beach last month.

Initial reports theorized that McGuire might have drowned or been taken by a shark. But Inspector Jaimie McClelland told the Examiner there's no evidence "at this stage" that a shark was involved.

Scott McGuire, 29, was snorkeling for lobsters when he went missing Sunday. Photo: Courtesy of New South Wales Police Force

When last seen Sunday, Scott McGuire was wearing red board shorts, black swim fins, black goggles and a clear snorkel.

A Facebook page called Find Scott McGuire has been created in an expanded effort to locate him.

New South Wales police are asking anyone who might have seen McGuire, or any fishermen who were at Birbubi Point on Sunday afternoon to call them.

"Given the length of time, if he's still out there, it's very unlikely that we will find him alive," Inspector Jaimie McClelland told the Examiner. "Until we find something more definite, it's still a search and rescue operation."

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