At least 4 people were killed in a bus crash in the U.S. state of Utah. Victims are from a Chinese tour group, according to local reports.

The incident happened around noon on September 20 local time. There were 30 people on the bus.

"Four have been killed, 12 to 15 others with critical injuries and 10 more with minor to serious injures," local police said. 

The injured have been sent to the hospital. An investigation is underway.