Andy Miller, a spokesman for Park City Mountain Resort where Burke was training, said he did not know the extent of her injuries. Burke was injured while training at the resort's Eagle Superpipe, Miller said.
"She sustained injuries, was stabilized on the scene by the Park City Mountain Resort mountain patrol and transported to the base patrol," Miller said.
Miller and other sources had little information. But ESPN, which runs the X Games, reported that Burke was injured in a fall and transported to University Hospital in Salt Lake City.
The Toronto Star reported Tuesday evening that Burke is in a coma.
And powder.com quoted an anonymous witness who said Burke landed on her feet at the bottom of the pipe after completing trick off the wall, but "whiplashed" over onto her side, obviously injured.
Burke is a member of the Canadian Freestyle Ski Team. She was preparing to defend her title at the Winter X Games in Aspen, Colo., later this month.
Her husband, Rory Bushfield, who is also a pro skier, tweeted early Tuesday evening to ask if anyone with a private jet could quickly fly him and Burke's mother from Vancouver to Salt Lake City.
Miller said the Eagle Superpipe is also where snowboarder Kevin Pearce was severely injured during training on Dec. 31, 2009.
The defending Winter X Games Women's SuperPipe champion, Burke has won four gold medals and four other medals at the X Games. Burke also won ESPN's ESPY award for best female action sports athlete.
Burke is a resident of Squamish, British Columbia, between Vancouver and Whistler, which played host to the 2010 Winter Olympics.