A woman driver was killed and her passenger was in extremely critical condition Monday afternoon after the car they were in crashed through a guardrail and plunged 75 feet into the Pennypack Creek in Northeast Philadelphia, police said.

About 1:30 p.m., the 2006 Lincoln Town Car was traveling south in the 8500 block of Krewstown Road when it failed to navigate a turn, crossed the northbound lane and plowed into the guardrail, said Chief Inspector Scott Small.

The car landed upside down in about three feet of water, Small said. The driver, a woman in her 70s, was pronounced dead at the scene. The passeger, a 71-year-old woman, was transported to Aria Health-Torresdale Campus.

Witnesses said the car was moving slowly when the accident occurred, Small said. The car was pulled out of the creek Monday evening and will be examined for any mechanical problems. Small called the road "extremely narrow and winding" and "pretty treacherous."

   -Robert Moran