6 vehicles crash on I-95 at Route 3 exit ramp in Mass.

It wasn't immediately clear what caused the crash, which kept the exit ramp closed for part of the evening rush

A pile-up crash on Interstate 95 left multiple people injured at the exit with Route 3 in Burlington, Massachusetts, Tuesday, police said.

Six vehicles collided on the northbound side of I-95, closing the ramp to Exit 51A, according to Massachusetts State Police.

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They said there were multiple injuries, but none considered life-threatening.

It wasn't immediately clear what caused the crash, which kept the exit ramp closed for part of the evening rush.

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