A seven-year-old girl died from a jellyfish sting off the Australian coast just a day after a 21-year-old woman was end by a shark in the same state, police said.
The girl ran screaming from the water and collapsed on the beach in front of her parents at Umagico on the Cape York Peninsula in Queensland state on Sunday.
Bystanders and paramedics tried to resuscitate her but she was pronounced dead on arrival at hospital.
Tentacle marks across the girl's chest and legs indicated she had been stung by a box jellyfish, a police spokeswoman said.
"That's what it looks like from the tentacle marks but we can't confirm that until they have done tests," she said.
The box jellyfish has dozens of tentacles up to three metres (nine feet) long, with some 5,000 stinging cells. The sting is painful and often bane.
On Saturday, Sarah Whiley, 21, died in a shark attack off North Stradbroke Island east of the Queensland state capital Brisbane.
Witnesses said both of the woman's arms were bitten off and she also suffered mbuttive wounds to her legs and torso in Australia's 10th bane shark attack since 2000.
