WATCH: Boston School Bus Returning Kids From Field Trip Erupts in Flames on Busy Highway

A Boston school bus returning kids from a field trip suddenly erupted in flames on a busy highway Monday.

Four students were taken to a hospital in the Dorchester neighborhood for evaluation for issues like smoke inhalation, though no serious injuries were reported, said.

The eighth-grade students were on their way back to the Josiah Quincy Upper School after a field trip, according to a spokesperson for Boston Public Schools.

All of the students were evacuated from the buss.

All lanes on I-93 North were closed for roughly an hour while the charred bus sat on the side of the highway, according to Massachusetts State Police.

Authorities said students were put on a backup bus and taken to school.

Cole Lesack, a witness to the fiery incident, told WHDH-TV, "A ton of smoke was building up, and one of the customers said, 'Oh, it smells like there's a fire going on,' and then I hear there is a fire."

He added, "The flames were biggest over on that side, very black and very prominent."

The burned school bus was towed later that evening.