PANGUITCH, Utah — Authorities on Saturday identified the four Chinese tourists killed in a bus crash in southern Utah, and the tour group is dispatching employees from China to help those injured.

Three women and one man perished in the crash on a highway running through the red-rock landscape of southern Utah on Friday. The victims have been identified as Ling Geng, 68, Xiuyun Chen, 67, Zhang Caiyu, 62, and Zhongliang Caiyu, 65. They were all from Shanghai, China.

They were part of a tour group made up of 29 tourists and one leader. They come from Shanghai and the nearby provinces of Zhejiang, Jiangsu and Heilongjiang, according to a news report on the media website huanqiu.com. The tour leader came from Hebei Province, near Beijing, according to the Zhejiang Online news site.

Five passengers remained in critical condition Friday night, and the death toll could rise, Utah Highway Patrol Sgt. Nick Street said.

All 31 people on board were hurt. Twelve to 15 on board were considered to be in critical condition shortly after the crash, but several of them have since improved, Street said. Not everyone was wearing a seatbelt, as is common in tour buses, he said.

The wreckage of a bus crash near Bryce Canyon National Park in Utah on Sept. 20, 2019. Spenser Heaps / The Deseret News via AP

The Shanghai Municipal Bureau of Culture and Tourism urged the travel agency, Shanghai Zhuyuan International Travel Agency, to spare no effort in rescuing the injured and properly handle the follow-up matters.

Phone calls to the travel agency rang unanswered Sunday morning. Lu Yong, the travel agency's general manager, told a Chinese TV program that the agency's American partners sent 10 staff members to hospitals to help the victims communicate with doctors and police.

The News Perspective program, part of the Shanghai Media Group, said in an article on its official social media account that seven relatives of the victims were expected to leave for the United States on Monday or Tuesday with travel agency staff and officials from the culture and tourism bureau.

The news program's social media post included photos of parts of the itinerary, indicating the accident occurred on the seventh day of a 16-day trip and also included visits to Yellowstone National Park, Salt Lake City and Las Vegas. They were to fly to the East Coast after the western U.S. stops.

The crash happened near a highway rest stop a few miles from southern Utah's Bryce Canyon National Park, an otherworldly landscape of narrow red-rock spires.

Authorities believe the driver swerved on the way to the park on Friday morning. But when he yanked the steering wheel to put the bus back onto the road, the momentum sent the bus into a rollover crash, authorities said.

The driver, an American citizen, survived and was talking with investigators, Street said. He didn't appear to be intoxicated, but authorities were still investigating his condition as well as any possible mechanical problems, he said.

There was some wind, but it was not strong enough to cause problems, Street said.

The crash left the top of a white bus smashed in and one side peeling away as the vehicle came to rest mostly off the side of the road against a sign for restrooms.

The National Transportation Safety Board was sending a team to investigate.

The company listed on the bus was America Shengjia Inc. Utah business records indicate it is based in Monterey Park, California. A woman answering the phone there did not have immediate comment.

Intermountain Garfield Memorial Hospital said it received 17 patients, including three in critical condition and 11 in serious condition. Patients also were taken to Cedar City and St. George hospitals.

Millions of people visit Utah's five national parks every year. Last year, about 87,000 people from China visited the state, making them the fastest-growing group of Utah tourists, according to state data.

More than half of visitors from China travel on tour buses, said Vicki Varela, managing director of Utah Office of Tourism.

The Chinese Embassy tweeted that it was saddened to hear about the crash and that it was sending staff to help the victims.

Bryce Canyon, about 300 miles (480 kilometers) south of Salt Lake City, draws more than 2 million visitors a year.

"You have a group from China who have worked hard to come to the states, got the visa and everything they needed, excited about it, and for a tragedy like this to happen it just makes it all the more tragic," Street said.