BURLINGTON, Mass. (AP) — A coach bus carrying 20 international students visiting Tufts University caught fire on Route 128 North in Burlington.

WCVB-TV reports that Lexington Fire Chief Derek Sencabaugh says the department responded Wednesday to a bus fire at Route 3.

The bus driver told firefighters that he thought he'd blown a tire so he pulled over. Then passengers began to see smoke coming from the back of the bus. There were no injuries.

According to a statement from bus company Local Motion, the fire started in the engine compartment but they are unsure of what caused the blaze.

Tufts University said in a statement, "We are grateful for the alert and calm response of the students, faculty, staff and the bus driver, which contributed to everyone emerging safely from the situation."

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