Friends of a man who died while free-diving off Moreton Island risked being attacked by a circling shark to retrieve their mate's body from the ocean floor.
The friends made the extraordinary decision to dive down 24 metres to reach the man, as a shark circled and apparently went for a fish on a speargun the man had been using.
Rescue Helicopter crewman Dan King, who responded to the drama on Monday, said it was an incredibly brave decision.
He said the friends had reported a shark was spotted in the water as their friend was free-diving.
It was unclear if the shark had "bumped" the man, or if it was simply attracted to the fish he was trying to catch.
Despite the threats to their own safety, the friends decided they weren't going to leave their mate on the sea floor.
"There was a shark around the gentlemen while he was under the water when he was sighted by his friends," Mr King told the ABC.
"They had seen the shark, yet they still decided they were going to go down and, by all accounts, seems to be an incredible job.
"They have dived down 24 metres holding their breaths and have grabbed hold of the gentlemen and have brought him back to the surface. As far as I am concerned it is an amazing effort."
The drama unfolded off the northern tip of the island about 11am on Monday.
The rescue effort was hampered by a large swell and the fact that three boats the men had been using were tethered by just one anchor, and at one point they began to drift.
Despite the best efforts of the friends, the man could not be saved.
Investigations into the incident are continuing.
Meanwhile, police have resumed the search for a father who went missing off the Sunshine Coast.
The 37-year-old was reported missing on Sunday afternoon after going for a swim off Peregian Beach.