Updated July 12, 2023 at 7:53 PM ET

Three people were killed and at least 14 others were injured after a Greyhound bus in Illinois crashed into three other vehicles, state police said.

Just before 2 a.m. local time Wednesday, the bus was traveling west on Interstate 70 near Highland, Ill., just east of St. Louis, and struck three commercial vehicles parked on an exit ramp to a rest area, Illinois State Police said.

Four people were taken to the hospital by helicopter, and at least 10 were transported by ambulance, all with serious injuries, the department said.

Greyhound said in a statement the bus was traveling from Indianapolis to St. Louis, and its driver was one of the people sent to the hospital.

"Our primary concern is ensuring we care for our passengers and driver at this time. We are working closely with local authorities," Greyhound spokesperson Mike Ogulnick said.

No one in the parked vehicles was injured, police said.

At about noon Wednesday, the police said all lanes of I-70 and the exit ramp had reopened, after the ramp and all but one lane of the interstate were closed earlier in the day.

There is an ongoing investigation into the incident, police said.

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