A total of 38 students and seven adults, including the driver, were taken to area hospitals, authorities said.
Some were in critical condition and undergoing surgery, they said.
The teacher, 51-year-old Jennifer M. Williamson, was a longtime Paramus native who taught in the district for nearly 20 years.
"That was my daughter's best-ever teacher," a mother of an unharmed student said. "She was an angel."
TRIBUTE: For each and every student of hers -- both current and former -- veteran middle-school teacher Jennifer Williamson made class worth going to during what were the most turbulent years of their young lives.
The bus was filled with 40 or so students and several adults, one of three buses on a field trip to Waterloo Village in Stanhope, a father of one of the victims told Daily Voice as he rushed to the hospital to check on his daughter.
"The other two buses were in front of them," the father of another student said. "They didn't see what happened."
District officials were receiving parents to provide information in the auditorium at East Brook Middle School in Paramus.
Meanwhile, Gov. Murphy attended a news conference with Bergen County Executive Jim Tedesco, school officials and police at Paramus High School.
"On days like this my late dad used to say 'Man proposes and God disposes as it relates to our plans," the governor told reporters, staff and parents.
"65 years I've lived in this town and it’s difficult to stand here to talk about an education community suffering so deeply," Tedesco added.
- All will be open on Friday, with crisis counselors on hand to assist children and staff;
- After-school activities were canceled Thursday and Friday -- aftercare will continue;
- All field trips canceled for the remainder of the school year.
Several victims were reported ejected in the crash shortly before 10:30 a.m. near the Waterloo Bridge (Exit 25) in Mount Olive, which knocked the bus off its chassis and onto a highway median.
Both directions of the highway were closed except for emergency vehicles, as dozens of EMS units, fire companies and law enforcement responded.
A request for medical choppers had to be canceled because of the weather.
Area hospitals were recalling all available emergency physicians.
Victims were brought to St. Joseph's Regional Medical Center in Paterson, St. Clare's Hospital facilities in Dover and Denville, Hackettstown Medical Center, Morristown Medical Center and UMDNJ in Newark.
The dump truck lost both fuel tanks, further complicating the response.
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