By Walt Hunter

UPPER DARBY, Pa., (CBS) — Upper Darby Police say frightened children, screaming for help from the windows of their school bus brought them racing to the corner of West Chester Pike and New Street around 2:30 p.m. Wednesday.

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Superintendent Mike Chitwood says the 21 children, ages 5 to 10, got scared after the bus, that was supposed to be taking them home from a West Philadelphia Charter School instead began skipping stops, and driving miles away into Upper Darby.

Chitwood says a driver who saw the children screaming for help aboard the bus near 69th Street Terminal dialed “911”. Officers then found the bus pulled over a few blocks west.

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According to the police Superintendent, the bus driver was “disoriented” and had gotten lost twice before driving into Upper Darby. The driver, police say, was taken to a local hospital for observation and testing.

Officers determined there were no injuries to the children, with the exception of a little girl who pinched her finger trying to open a bus window.

As the children were transferred to another bus and dropped off at their normal locations, School District officials say the driver was a substitute on the route. They say they are now investigating to find out what what happened and to determined the source of the driver’s medical problems.

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A spokesperson for All-City Transportation, the company that operates the bus under contract to the school district, told CBS 3 the company is aware of the incident, but would have no further comment.