Updated

A marine biologist killed in a shark attack had calmly fought off the predator before it returned and pulled him deep into the water, his diving partner said Thursday.

Police have abandoned the search for the body of 23-year-old Jarrod Stehbens (search) following the attack Wednesday off Glenelg Beach on Australia's south coast — a region that has seen five fatal shark attacks since 2000.

"Jarrod fought it off initially, then it came back again and grabbed his leg and just took him deeper," Stehbens' diving partner, Justin Rowntree (search), said Thursday.

"He seemed quite calm — he was trying to get his leg out of its mouth," he added.

Rowntree and Stehbens, both marine biologists at the University of Adelaide (search), were diving to collect cuttlefish eggs when the shark attacked close to a popular beach in the city of Adelaide. The men were 16 feet from the surface in water 60-feet deep.

Rowntree said he felt helpless in the few seconds before his colleague was dragged to the depths and out of sight.

"Lots of things were going through my mind," Rowntree said. "I just hoped, I just hoped that he'd come up."

Two research colleagues on a boat above did not see the shark approach. Rowntree sensed no danger even when the predator brushed past him.

"I thought it was a dolphin," Rowntree said. "It just nudged my side and I looked around [and saw] just a big white mass."

Rowntree surfaced and was hauled to safety by his colleagues who had by then seen the shark's tail fin slice through water's surface. No trace of Stehbens has been found except for his air tank and buoyancy vest.

The attack, only eight months after an 18-year-old surfer, Nick Peterson, was killed by a 16-foot great white shark at nearby West Beach, led locals to complain that the protected species is posing a growing menace along Adelaide beaches.

The victim's father, David Stehbens, held a news conference Thursday in which he described his son as an experienced diver who knew the underwater environment.

David Stehbens said he had discussed with his son the merits of a shark cull in December when Peterson was killed while being towed on his surfboard by a motorized dinghy.

"He's a marine biologist; he wouldn't want anything killed like that," the father said.

Local fisherman Keith Klemasz said diving was unsafe in the area because so many fishermen dump fish guts and waste in the water.

"It is crazy; they [divers] are shark bait," Klemasz said.