New London — Parts of State Street in downtown New London were closed to traffic Wednesday afternoon as fire officials investigated reports of a strong smell of gas in a commercial building.

An employee at Spark Marketplace, located at 225 State St., called the fire department at 12:09 p.m. to report a strong odor of gas in the building, according to New London Fire Department officials.

The fire department arrived to investigate the odor and Eversource was called to the scene. A ladder was put up to the roof of the building so fire officials could ventilate and check heating equipment on the roof.

Investigators found that a malfunctioning gas heating appliance was causing the smell inside the building. The appliance was taken out of service by Eversource, fire officials said.

No injuries were reported and only one person was working in the building, so no evacuations were necessary. State Street was reopened to traffic after about 30 minutes, according to the fire department.