IRWIN TWP, Venango County - A Harrisville area woman was seriously injured Monday night when an alleged drunken driver struck her car on Route 8 near the Butler County line, state police said.

Sonya Haag, 28, of Irwin Township was returning home from work at a Grove City nursing home about 10 p.m. when a pickup truck slammed into her car.

Haag suffered severe head injuries and was flown by medical helicopter to Presbyterian Hospital in Pittsburgh, according to authorities.

She was listed in critical condition early this morning, according to a hospital spokeswoman.

Gerald Henwood, 34, of Franklin faces numerous charges in the crash, including felony assault by a vehicle and driving under the influence.

Police said Haag was driving a Pontiac coupe southbound on Route 8, about one mile south of Route 208, when she slowed to turn into the driveway at her home.

A nurse's aide at the Grove Manor nursing home, Haag had just finished her shift and was returning home, said Randy Haag of Irwin Township, the woman's uncle.

Henwood also was driving south on Route 8 when his Ford Ranger pickup struck Haag's car, forcing the vehicle forward about 50 feet and into a ditch, police said.

The car traveled another 45 feet before it stopped in the northbound lane facing west. The pickup also ended up in the northbound lane, facing south, police said.

Henwood, who suffered minor injuries but refused medical treatment, was arraigned on charges before District Judge Robert Boyer.

In addition to DUI and aggravated assault by a vehicle, Henwood is charged with possession of a small amount of marijuana and drug paraphernalia, as well as several other traffic violations.

Police said both drivers were wearing seat belts.