The tragic accident took place in her primary school Devonport, on her island Tasmania.
The children they fell from a height of about ten meters. Two boys and two girls, aged about 11, were killed and five others were seriously injured, four of them in critical condition, according to Tasmanian police.
The Australian Prime Minister Scott Morrison described the accident as "heartbreaking". "Young children had gone out to have fun with their families, and instead we had such a horrific tragedy this time of year. "It breaks your heart," he said.
The meteorological service provided "Weak winds" and sunshine today - as the summer of the southern hemisphere begins - in the area where the tragedy unfolded, on the north coast of Tasmania.
The first aid services, with the support of helicopters, had rushed to the scene of the tragedy around 10:00 (local time; around 01:00 Greek time) at Hilkrest School in Devonport, Australia's third most populous city.
The Prime Minister of Tasmania Peter Gatwin said it was "unthinkable" that "this shocking tragedy" had taken place and promised that an investigation would be carried out.