Seventeen firefighters responded to the northbound I-476 off-ramp near Lancaster Avenue around 7 p.m., where they found the school bus engulfed in flames, the Radnor Fire Company said.
The driver and an unspecified amount of students had evacuated and walked over to the high school, fire officials said.
No injuries were reported and the scene was cleared by 8 p.m.
The cause of the fire was not immediately known.
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