Several trucks were doused with a flammable substance and some were lit on fire in North Haven on Friday.
Firefighters were called to Powdered Metal Drive around 11:30 p.m. after getting a report of an explosion with visible fire. The original 911 call was reported by a resident on Frost Drive, they said.
When crews arrived to the business, they said they found a tractor-trailer fully involved with fire.
Investigators said several other trucks nearby were lit on fire and/or were doused with a flammable substance.
The North Haven Fire Department is investigating this incident as arson with the North Haven Police Department.
Anyone who witnessed the incident or anyone with helpful information is asked to contact North Haven Fire Department. Callers can remain anonymous.