Police are investigating a large crime scene in Waltham.

Officers were called to Lyman St. around 1:30 a.m. They blocked off the road with crime scene tape from Summer St. to Main St.

Boston 25 News crews at the scene saw police K9s and drone units assisting Massachusetts State Police and Waltham police at the scene.

Police have not said what they are investigating.

This is a developing story. Check back for updates as more information becomes available.

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