A three-year-old child is in a critical condition in Canada after a violent thunderstorm launched an inflatable house into the air with a number of kids trapped inside.

The storm swept through the Greater Montreal area Sunday afternoon, wreaking havoc on Ouellette Park in the borough of LaSalle as it dramatically launched the inflatable into the air before it came crashing down.

Paramedics evaluated 11 people, six of whom were sent to hospital, including four adults and two children, CTV News reported.

“All of a sudden, we see this dark cloud coming towards us,” witness Rosella Peluzzo told the network. “A lot of wind came towards here, chairs started flying, tables started flying.

“I see the inflated house, and it went up high, at least 40 feet, I would say. It was just turning up in the air.”

A borough worker said officials believe the inflatable flew around 12 feet into the air before it slammed down into the ground.

Global News reported late on Monday that the toddler remains in a critical condition after the accident, which took place at 4:25 p.m. local time on Sunday.

Peluzzo said people rushed to rescue the children inside after the bounce house landed back on the ground

“They were hurt, and I know that they were all sent to the Children’s Hospital,” she said.

Nancy Blanchet, the Mayor of LaSalle, said she was “deeply saddened to learn of the tragic accident that occurred late afternoon during a family gathering at Ouellette Park”.

“My heart goes out to the families, loved ones, and everyone affected, directly or indirectly, by this terrible event. On behalf of myself, my fellow elected officials, and the entire borough community, we offer them our full support during these extremely difficult times. Our entire community is deeply shaken by this serious accident.

“Please know that the safety of the public, particularly that of children, remains a priority. Any necessary measures will be considered in light of the findings that are established.”

On the weekend, ECCC had issued a severe thunderstorm warning for Montreal and nearby areas, with the storm expected to be “capable of producing strong wind gusts, up to quarter-size hail and heavy rain”.

It added: “Take immediate cover if a thunderstorm approaches. If outside, protect yourself from flying debris and hail.”

The bounce house accident occurred the day before Canada’s hurricane season officially begins, in which Environment and Climate Change Canada (ECCC) anticipates around eight to 14 named storms and three to six hurricanes to strike.