Authorities are investigating the cause of a "suspicious" two-alarm house fire that injured two people, including a firefighter, Sunday night in Trenton.

Firefighters from Trenton and other nearby towns responded to the blaze, which broke out around 6:45 p.m. on the 900 block of Genesee Street, NJ.com reported.

"Investigators at the scene noticed that the fire was present both inside and outside of the house, indicating that the flames could be suspicious and possibly started with an accelerant," Fire Director Qareeb Bashir told NJ.com, explaining that the fire spread quickly through the residence.

The fire critically injured one male resident of the home who was transported to a medical center in Philadelphia. In addition, a firefighter that fell through the floor while trying to contain the blaze also sustained minor injuries and was transported to St. Francis Medical Center in Trenton, NJ.com reported.

Investigators from the Mercer County Prosecutor's Office are working with detectives from the Trenton Police Department and the Trenton Fire Marshal Unit to determine if the fire was accidental or arson.

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