Four people died when a tour bus carrying Chinese tourists crashed Friday near Bryce Canyon National Park in Utah, officials said. Another five people were in critical condition.

The crash occurred on state route 12 at around 11:30 a.m. local time, about 3.5 miles west of the park, according to authorities and the park. The Chinese embassy said the tour bus contained Chinese tourists. Five people were in critical condition and several more with injuries described as minor to serious were stable, the highway patrol said.

"The bus was traveling east. It appears like he drifted off to the left-hand side of the road. Possibly over-corrected — something happened, the bus flipped over, overturned," Garfield County Sheriff Danny Perkins said, according to video from NBC affiliate KSL of Salt Lake City.

The bus "ended up rolling, and it rolled actually into a guardrail which impacted the bus approximately in the middle of the bus area,” the sheriff said.

The Utah Highway Patrol confirmed later Friday that it believes the driver drifted off the road to the right, over-corrected to the left and the bus rolled one time and landed on the guardrail.

We had a horrible bus accident in Garfield County today. I would like to thank the multiple agencies that assisted us. I also want to thank our volunteers who done an exceptional job and most certainly save lives. Also our prayers are with those who lost loved ones today. pic.twitter.com/n4IY7AUOrz — Danny Perkins (@sheriffdperkins) September 20, 2019

There were 31 people on the bus, 30 of whom are Chinese nationals, and the driver is among the injured, the highway patrol said. The patrol initially said there were between 12 to 15 critical injuries.

The Chinese embassy in the United States tweeted that "we are saddened to hear about the accident in Utah involving a bus carrying Chinese tourists." It thanked first responders and said it has sent personnel to provide any assistance to victims.

Garfield County Commissioner Leland Pollock told told KSL that he feels terribly for those involved in the crash.

"This is pretty overwhelming for a little county of 4,900 people," he said. "This is just horrible for us."

The highway patrol said multiple air ambulances and rescue crews were dispatched to the scene and said state route 12 was closed as authorities investigated the crash. The highway was later reopened, the highway patrol said.

Bryce Canyon National Park is in southern Utah and is known for its unique geology, according to the National Park Service website.

Perkins, the sheriff, said that law enforcement has practiced for crashes like Friday's and that "we've been worried about this. We've talked specifically about tour buses getting in a wreck because we have so many tour buses."

Bryce Canyon National Park gets more than 2 million visitors a year. In 2018 the park has a little more than 2.6 million recreational visitors, according to National Park Service statistics.

"I guess you're never, you're never prepared for something like this totally," Perkins said, but he said that people came together after the crash and did a great job responding to it.

Perkins said ambulances from all over the area responded, and there were offers of assistance from law enforcement agencies in other jurisdictions after the deadly crash. "When things happen in these rural areas ... we come up with a lot of resources if we need to," he said.

A firefighter who responded to the scene speaks fluent Chinese, which helped first responders, and nearby Ruby's Inn has a workforce from all over the world and were also able to help with translation after the crash, Perkins said.

The highway patrol said that it was working with the Chinese embassy to assist the injured as well as to notify family members in China.