By Jim Melwert

DOYLESTOWN, Pa. (CBS) — A 36-year old Bucks County woman has pleaded guilty to being under the influence of drugs when she caused a crash that killed a 71-year-old woman in Horsham, Pa., last fall.

Kelly Sanfratello, of Quakertown, Pa., was behind the wheel of a Jeep Wrangler when she ran a red light at the intersection of Easton Road and County Line Road, about 7pm on November 21st of last year.

Her vehicle hit a Nissan Rogue driven by Anne Marie Schnerr, of Bristol, Pa.   Schnerr was pronounced dead at the scene, and four other passengers in her car were injured.

Investigators say the light had been red for seven seconds before the crash, and tests showed that Sanfratello had amphetamines in her system.

Sanfratello pleaded guilty to homicide by vehicle, DUI, four counts of recklessly endangering another person, and failure to stop at a red light.

She’s out on bail pending sentencing.