CLAY TWP — A medical helicopter flew one of four people injured in a head-on crash to a Pittsburgh hospital Tuesday evening.

The crash occurred at 6:30 p.m. on Route 8, just north of the Rock House, according to state police.

Police said Dana Powers, 33, of Slippery Rock was driving a Chevrolet Malibu south on Route 8 when her vehicle traveled into the northbound lane and oncoming traffic.

The Malibu crashed head-on into a 2007 Chevrolet Sonic driven by Jennifer A. Bopp, 26, of Cabot.

Powers and Bopp were injured as well as Bopp’s passengers, Destiny Stemmerich, 20, of Slippery Rock and Daniel Hartzell, 28, of Cabot.

Powers, who was wearing a seat belt, suffered only minor injuries and was not transported to the hospital.

Injuries to everyone in the Sonic were described as moderate, and they all were transported to the hospital. However it was not immediately clear which people were transported by ambulance and which injured person was flown by helicopter to Allegheny General Hospital in Pittsburgh.

Officials at the Pittsburgh hospital this morning said Hartzell was the only person in the accident to be a patient, and he was in good condition.

Unionville Fire Chief Nathan Wulf said the helicopter landed outside the Unionville Fire Department building.

Firefighters from the Unionville and West Sunbury departments redirected traffic around the accident, Wulf said.

Butler and Slippery Rock ambulance services responded to the accident.

State police said Powers would be cited with a traffic violation.