A two-alarm fire broke out at the Nelson Building at 100 Main St. on the evening of Jan. 31. Courtesy photo

NASHUA – Approximately 30 residents were evacuated during a two-alarm fire at 100 Main St. on the evening of Jan. 31.

According to Nashua Fire Rescue, firefighters responded to the historic Nelson Building shortly before 10 p.m. Upon arrival, they found fire in apartment 14 on the second floor of the four-story mixed-use building.

A second alarm was struck to assist with the evacuation.

Firefighters with Engine 1 conducted “aggressive fire attacks” to bring the blaze under control.

The building’s smoke detectors and sprinkler system were both in working order. No injuries were reported; however, a number of apartments remain uninhabitable.

Additional information was not available as the fire remains under investigation by the state Fire Marshal’s Office.

The building is owned by Whiting Building LLC and is valued at $5.9 million.