A 14-year-old girl claims that the taxi driver who took her from her grandmother's house in North Philadelphia to her parents' house in Juniata Park on Tuesday night made an unthinkable detour when he parked on a dark street and sexually assaulted her, police said.

The girl told police that she called for a cab about 9:50 p.m. to pick her up at her grandmother's house on Sydenham Street near Venango, said Special Victims Unit Lt. Anthony McFadden.

While en route to Juniata Park, she claims, the cabbie pulled over in Northeast Philadelphia and assaulted her, police said. Authorities declined to detail the exact nature of the alleged sexual assault.

Following the attack, the cabbie drove her to her destination and drove off, police said.

The girl's parents called police about 12:10 a.m. yesterday, and she was taken to St. Christopher's Hospital for Children, where a sexual-assault examination was conducted, police said.

SVU Capt. John Darby said that no one has been arrested, although police know who the cabbie is. He said that the teen was scheduled for further questioning last night.