Parents are being warned to keep their children out of the water during stinger season after a six-year-old boy died on the Tiwi Islands, north of Darwin.
Witnesses told police the boy ran from the water saying he had been stung by something.
It is believed to havebeen a Box Jellyfish.
The boy collapsed and was taken to the local clinic but staffs were unable to resuscitate him.
Professor Bart Currie, from the NT Department of Health and Community Services, said the death was a sad reminder about how dangerous it was for children to swim in the sea during the stinger season, which runs from October to May.
"Box Jellyfish are dangerous and severe stings can be fatal, particularly for children," Prof Currie said.
"Children are more at risk due to their small body size and parents should be vigilant in keeping their children out of the sea during the stinger season."
Of the last 11 deaths from jellyfish stings in the Territory all have been children.
The most recent death in the NT was in 1996 when a three-year-old girl was stung on a remote beach.
An autopsy will be conducted to confirm the cause of death on the Tiwi Islands and a file prepared for the coroner.
Prof Currie said in the event of a Box Jellyfish sting, the affected area should be soaked with vinegar before removing tentacles and seeking professional
