THE Crocodile Man, Steve Irwin, is dead. He was killed in a freak accident in Cairns, police sources said. It appeared that he was killed by a sting-ray barb that went through his chest, Queensland Police Inspector Russell Rhodes said.

He was swimming off the Low Isles at Port Douglas filming an underwater documentary and that's when it occurred.

Ambulance officers confirmed they attended a reef fatality this morning at Batt Reef off Port Douglas.

Mr Irwin was killed just after 11am,  Eastern Australian time.

It is understood he was killed instantly.

A source said Mr Irwin was already dead when his body was brought onto the Isle.

A source said Mr Irwin's body was being airlifted to Cairns Hospital in North Queensland for formal identification.

An Emergency Services Response Management spokeswoman said they received a call about the tragedy at 11.11 am,  Australian Eastern Standard Time.

The response unit left in a helicopter for the Batt Reef at 11.18am and arrived shortly after.

Mr Irwin was pronounced dead at the scene immediately, the spokeswoman said.

Steve Irwin RIP 1962 - 2006