What does it mean when a school bus is stopped on a roadway and its red lights are flashing?

When a stopped school bus is flashing its red lights, all traffic approaching the bus from any direction must stop at least 20 feet away from the bus. You may not resume driving until the red lights stop flashing or when the bus driver or a traffic officer signals that you can proceed. In New York State, you must stop for a school bus even if it is on the opposite side of a divided highway.
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