Four children were killed and several others were injured when an Australian school children fall into the air while jumping on a bouncy castle at an outdoor playground, foreign media reported.

Police said this happened in an elementary school in northern Tasmania was about 10 meters (33 feet) high when students were celebrating the last week of class before the Christmas holidays.

“I can sadly confirm that four children have died and four are in critical condition and one is in critical condition,” said Tasmanian Police Commissioner Darren Hein.

The victims were two boys and two girls in grade six, all of whom were about 11 years old. The incident took place at Hillcrest Primary School on Thursday around 10 a.m. local time.

 On the day of the incident, local meteorological services forecast “light winds” for the area across the cold Bass Strait off the northern coast of Tasmania. But there was a strong wind at the time of the accident.

Several rescue helicopters and ambulances arrived at the scene to take the injured to hospitals after the incident.

The officers described it as a “very sad scene” and the photographs show police officers covering up with tears and blue tarpaulins and taking away the bodies. Prime Minister Scott Morrison said the incident was “heartbreaking”. A police investigation is underway.