A four-year-old girl and six-year-old boy died after they were found unconscious in the Swan River near where revellers had gathered for new year celebrations and close to a children's playground.
The pair, from separate families, was spotted in the water at a popular family picnic spot in Burswood Park, 3km east of Perth, about 5.25pm on Sunday.Â
They were unresponsive when members of the public pulled them from the river.
Despite the efforts of nine paramedics and doctors at Perth Children's Hospital, the children could not be revived.
WA Liberal Leader Libby Mettam on Tuesday called on Police Minister Paul Papalia, who has oversight of the Burswood Park Board, to launch an independent review into the deaths.
There are claims no action was taken when safety concerns about the park were previously raised with the board, Ms Mettam said.
"It is horrifying to learn that concerns have been raised and seemingly nothing done about them," she said.
"There must be transparency about the government's response, or lack of response, to any safety warnings."
The review must examine additional safety precautions for the park for any future large events close to the river, the Liberal leader said.
"We obviously can't fence the river but where there are playground facilities like these so close to the water, we must ensure they are safe and secure."
The thoughts of every West Australian are with the families of these two children, Premier Roger Cook said.
"I simply cannot imagine their grief," he said.
Police officers assigned to the Coronial Investigation Squad have taken carriage of the investigation and the premier said the government will closely examine the findings
"We will also ask Burswood Park Board to consider any changes that could improve safety in the area."
The park board has been contacted for comment.
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