Veteran Swimmer "Taken" by Shark in Australia

Authorities in the Australian beach town of Tathra believe a women was "taken by shark" Thursday morning while she was participating in a group swim.

Christine Armstrong, 63, was an experienced swimmer who regularly trained in the mornings by swimming from the New South Whales beach to a fishing wharf some 600 meters (656 yards) offshore.

Armstrong was with a group of swimmers, including her husband, when she was apparently taken by what authorities described as a large shark, estimated to be about 3.5 meters (11 feet) long.

News reports from Australia indicate the group of about half a dozen swimmers had reached the wharf and had turned around to head back to shore when they noticed Armstrong was missing.

"As they were coming back they observed a 3- or 4-meter shark in the water, they gathered together for protection and made their way back to the beach," Inspector Jason Edmunds of the Far South Coast Command, told CNN.

When the group realized Armstrong did make make it back to shore, they contacted emergency workers.

A witness on the beach told authorities that he saw a large shark that was apparently mauling something in the vicinity of where the swimmers were.

Tathra beach was closed to swimmers Thursday, but poor conditions later in the day caused the search for Armstrong to be suspended until Friday morning.

Armstrong and some of her fellow swimmers were lifeguards and members of the Tathra Surf Live Saving Club.

"Club members involved in the incident are receiving counseling and it is expected that this unfolding tragedy will impact significantly on the small coastal community," the club said on its website.

According to the Canberra Times, the Tathra Surf Live Saving Club had issued a warning in 2012 that fishermen using the local wharf were endangering the lives of swimmers by fishing for sharks.

The waters, however, were not known to be frequently visited by sharks.