NEW SALEM, Pa. (AP) _ An 11-year-old girl was abducted from a school bus stop at knifepoint and tied to a tree for more than two days until she wriggled free, police and relatives said.

Cassie Pennington freed herself Sunday afternoon and walked along a road for at least five miles, then hid in weeds overnight before making it to a trailer home on Monday morning and calling her parents, said her mother, Michaelene Pennington.

''She seems like she's holding up a lot better than the rest of us,'' Mrs. Pennington said. ''We're amazed, just amazed at the strength she has.''

Cassie was taken to a hospital for treatment.

She told her mother the man who kidnapped her was sitting in a car at the bus stop Friday morning when she walked up.

''If he wouldn't have had a knife she would have run. She did what she had to do to survive,'' Mrs. Pennington said.

The man drove several miles to the woods, where he tied the girl up and left her. He returned Saturday, Mrs. Pennington said. ''He came and he told her, 'People are looking for you.' ... She could hear helicopters.''

Over the weekend, about 100 volunteers hunted along roads and through woods and abandoned buildings around New Salem, which is 40 miles south of Pittsburgh. A reward fund was set up.

No arrests were made.