Three victims of a crash involving a 1930-era airplane at Abbotsford Airport on Saturday have been treated and released from hospital.

The other two occupants of the vintage biplane, including the pilot, have been upgraded to stable condition.

The plane, a de Havilland Dragon Rapide, “experienced difficulties on the airfield” shortly after airshow events had concluded for the day, according to the Abbotsford International Airshow. This allowed first-responders, who were already on the scene, to get to the plane quickly.

Witness David Kent told CTV Vancouver that the "older-style airplane" could be seen rocking from side to side before its wing clipped the ground. He said it smashed nose-first into the runway.

“It hit hard nose down and I thought, ‘There will be injuries. I hope there are not too many people there and I hope there’s no fire,’” Kent said.

Officials from the Abbotsford International Airshow said that the plane was from a museum in the United States and part of a series called “Living History Flights,” which had been taking place alongside the airshow.

“Some of these museum aircraft offer rides to people,” Jim Reith, the airshow president, said. “There are a lot of airshow attendants who are interested to take rides in vintage aircraft, so it was part of that program.”

On Sunday morning, investigators from the Transportation Safety Board of Canada were called in to determine the cause of the crash, which remained unknown.

“We’ll be looking at the aircraft and trying to determine if there was anything wrong at the time, how the aircraft is broken up and the sequence of the accident,” Yanick Sarazin, the regional manager of the Transportation Safety Board of Canada, told CTV Vancouver.

The final day of the airshow went ahead as planned on Sunday, but all “Living History Flights” were cancelled.

With files from CTV Vancouvers’ Ben Miljure and the Canadian Press