ATTLEBORO — Fire Chief Scott T. Lachance reports that the Attleboro Fire Department swiftly extinguished a house fire late Saturday night, marking the city’s second structure fire in less than 24 hours.

At approximately 10:58 p.m. on Aug. 9, crews were dispatched to 21 Greenwich St. for a reported house fire. Upon arrival, firefighters encountered heavy flames at the rear of a two-story, single-family home with an attached in-law apartment.

Engine 2, which was already in the neighborhood following another emergency call, arrived within two minutes. Firefighters quickly attacked the blaze from the exterior before moving inside to douse remaining hot spots. Their efforts successfully contained the fire to the second-floor in-law apartment.

All residents evacuated safely before crews arrived. Two individuals were transported to Sturdy Memorial Hospital for evaluation of possible smoke inhalation and later released. The occupants of the affected apartment will be temporarily displaced. No firefighter injuries were reported.

“This fire had the potential to spread much further,” said District Chief Scott Godin. “Thanks to Engine 2’s proximity and fast action, the fire was confined before it could cause extensive damage.”

Mutual aid assistance on scene and for station coverage was provided by the North Attleborough, Seekonk, Pawtucket, and Norton Fire Departments. Firefighters cleared the scene at about 12:45 a.m.

Investigators determined the fire was accidental, caused by the improper disposal of smoking materials.

The incident followed a separate two-alarm fire early Saturday morning at El Buen Sazon restaurant on Pine Street, which was declared a total loss. That investigation remains ongoing.