HAMDEN, Conn. (WTNH) – A CT Transit electric bus caught fire in the parking lot of the department Saturday morning, according to fire officials.

The Hamden Fire Department responded to the lithium ion battery fire at 2061 State St. The bus was unoccupied when it caught fire.

Officials said the fire was difficult to extinguish due to the thermal chemical process that produces great heat and continually reignites. Firemen had to use “copious” amounts of water to extinguish the flames, according to Assistant Fire Chief Jeffrey Naples.

Two CT Transit workers were transported as a precaution from exposure to the smoke, and two firefighters were transported for heat exhaustion, officials said. All were released from the hospital following treatment.

CT Transit Interim Deputy General Manager Josh Rickman said the bus involved in the fire was purchased and delivered in 2021.

The cause of the fire is currently under investigation by the Connecticut State Police Fire and Explosion Investigative Unit. There is no criminal aspect to the fire at this time.

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