Primary school children fall 10m from jumping castle caught in gust

Tasmania's police commissioner has described the tragedy which claimed the lives of the year five and six pupils as heartbreaking.

Commissioner Darren Hine spoke in Devonport on Thursday afternoon saying that he could confirm four children, two boys and two girls, had died as a result of the incident about 10am.

"Another five suffered critical or serious injuries and are in hospital. They were grade six students," Commissioner Hine said.

"On a day where these children were meant to be celebrating their last day at primary school, instead we are all mourning their loss.

"Our hearts are breaking for the families and loved ones, school mates and teachers of those children taken too soon.

"Our thoughts are with the staff of Hillcrest Primary School and wider school community as well as those emergency services who attended the scene as first responders."

Police issued a statement later on Thursday evening saying a fifth child had died.

Several rescue helicopters were used to transport the children after police units and multiple ambulance crews rushed to the scene.

"Several children fell from the jumping castle. It appears they may have fallen from a height of approximately 10 metres," Commander Debbie Williams told reporters at the scene in Devonport.

"This is a very tragic event and our thoughts are with the families and the wider school community and also our first responders.

"This has been a very distressing and confronting scene."

The school announced on Facebook it was closing for the remainder of Thursday and asked parents to urgently collect their children.

Hillcrest Primary was holding a "Big Day In" celebration to mark the end of the school year.

Members of the public have been told to avoid the area.

Police on Thursday afternoon said there were a number of witnesses to the event, and that a more exact number would be determined by an investigation.

Traumatised parents had earlier that morning rushed to the school to collect their kids after they heard about the incident, not knowing if they were OK.

Frantic parents and grandparents were desperately asking if anyone had seen their children.

Parents, neighbours, children and school staff were crying with shock and horror as they watched emergency services flood into the school.

They watched on as ambulance officers treated several injured children behind a blue tarp erected near a tree at the bottom of a hilly embankment.

A shocked witness who lives across from the school said he had seen several children on the ground as he watched the terrible events unfold from his front balcony.

He said his wife had heard a "big bang," which drew their attention to the school oval.

"There was a strong gust of wind out of the blue, and I could see the jumping castle going up," neighbour Bob Smith said.

Mr Smith said he saw the inflatable jumping castle set up for what was to be a lovely day of entertainment and fun.

He said it was awful to think what had happened.

The shaken mother of a grade three pupil said she first heard about the incident while she was Christmas shopping at the Kmart.

"My father-in-law called me, and I swore at the top of my lungs," she said.

"You think the worst. It's just horrendous. You don't expect this to happen in your own neighbourhood.

"You see these things on the news happening elsewhere when things go bad."

She said her son's class had been waiting for their turn on the jumping castle just before the tragedy.

Her son said his class was meant to be the first to go on the attraction but were held back until grades five and six had their go on the jumping castle.

The mother said she was thankful her son was safe but felt terrible for the parents of children on the jumping castle when the wind struck.

Commissioner Hine said police and WorkSafe investigations would continue into the amount of children on the castle at the time, and how it had been secured down.

He said the investigation would take "quite some time" and a number of people and witnesses needed to be interviewed.

"Our focus now is supporting those who are tragically affected by what's happened," he said.

Tasmanian Premier Peter Gutwein passed on his thoughts to the community.

"It is difficult to find the right words," Mr Gutwein said.

"I'm sure I speak for all Tasmanians when I extend our deepest sympathies to all of the family and friends."

He said it was inconceivable to think something like this could happen on a day when the students were celebrating the end of the school year.

Prime Minister Scott Morrison described the accident as unthinkably heartbreaking.

"Young children on a fun day out, together with their families and it turns to such horrific tragedy. At this time of year, it just breaks your heart," he told reporters on the NSW Central Coast.

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