At least 20 children -- all of them 3- and 4-year-olds enrolled in the Centerville Head Start program -- were on the bus when the shot was fired at about 3:30 p.m. EDT Thursday, the Philadelphia Daily News reported.
"Parents were understandably upset," said Merilee Rutolo, the director of the Head Start program. "The children actually were very strong, and many of them really weren't aware of what occurred."
The shooter was apparently firing toward a housing project in the area, KYW-TV, Philadelphia, reported.
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