Queensland state government sources quoted by Australian Associated Press (AAP) said Irwin, 44, whose television show “The Crocodile Hunter” won international acclaim and popularized the phrase “Crikey,” was believed to have been killed by a stingray barb that pierced his chest.
He was filming an underwater documentary off Port Douglas when the accident occurred, the report said.
Sky Television also reported that Irwin had been stung by a sting ray.
Australian emergency officials could not immediately confirm the reports.
Irwin won a global following for his daredevil antics but also triggered outrage in 2004 by holding his then one-month-old baby while feeding a snapping crocodile at his Australian zoo.