WABC-TV(MOUNT OLIVE, N.J.) — A child and a teacher were killed when a school bus full of fifth-graders collided with a dump truck and slammed off a New Jersey highway on Thursday morning, the governor said.

Two officials briefed on the crash told ABC News that authorities are investigating whether the school bus driver made illegal U-turn before the deadly crash.

Photos of the chaotic scene show the school bus on its side in the median of Route 80 near Mount Olive Township, which is about 50 miles west of New York City.

The students — fifth-graders at East Brook Middle School in Paramus, New Jersey — were on the way to a field trip at the time of the collision, New Jersey Gov. Phil Murphy said at a news conference from the middle school.

Seven adults, including the driver, and 38 students were on board the bus, Murphy said, and 43 people of those 45 were injured and hospitalized.

Some patients are in critical condition and undergoing surgery, Murphy said.

“Our hearts are broken by today’s tragedy,” he tweeted.

Mount Olive Mayor Rob Greenbaum called the accident “horrific” in an interview with ABC New York station WABC-TV.

New Jersey state troopers used cadaver dogs to search for victims who may have been ejected, WABC-TV reported.

Multiple ambulances were on the scene and police said Route 80 was closed in both directions.

This story is developing. Please check back for more updates.

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