The hospital in nearby Brockville said on Twitter that it had received five patients, all in critical condition.
“We have a Mandarin translator onsite to support them,” it added in a post.
Joshua McNamara, a spokesman for Ontario’s air ambulance service, said that it flew three people farther west to Kingston. The Ottawa Hospital, which operates hospitals at three sites, said on Twitter that it was treating three bus crash patients. It reported that one was in critical condition and two were in serious but stable condition.
Eight other people were treated at a small hospital in Kemptville, and all were in stable condition, officials said.
Emergency service radio calls indicated that many of the passengers suffered lacerations.
Mr. Liang said that Union Tour Express, which has its headquarters in Peabody, Mass., and another office in New York City, has 18 buses and caters to tourists from China who are visiting North America.
He said this was the first serious crash the company has had in its seven-year history. The driver of the bus involved in the crash, he said, has worked for the company for about one month and worked as a bus driver elsewhere for about a year. He did not know the age of the bus involved in Monday’s crash.