WESTPORT — Fifty cats and dogs were rescued, and occupants of a second-floor apartment jumped to safety, when a blaze erupted in a Post Road East building late Wednesday.

Fire in the building housing the Townhouse for Dogs & Cats, 1040 Post Road East, was reported about 11:45 p.m. Wednesday.

Flames were erupting from the mixed-use building when firefighters arrived on the scene. Units initially dispatched to the scene included  Engines 2 and 5, Truck 1 and the shift commander, according to the report by Assistant Fire Chief Jeffery Gootman. Engines 4 and 6 also were subsequently sent to the scene.

“Heavy fire” was reported on the structure’s second floor, where an apartment with three residents was located.

The animal boarding business was located on the building’s first floor and basement.

The second-floor apartment’s occupants were awakened by smoke detectors, but found the exit blocked by fire.

They escaped the flames by jumping to safety and were treated at the scene by Westport EMS personnel, according to the report. The occupants did not have to be brought to a hospital for additional treatment.

Firefighters and police officers also removed the 50 dogs and cats being boarded at the business.

Firefighters deployed two hose lines to attack and extinguish the flames.

No injuries were reported.

The cause of the fire is being investigated by the Fire Marshal’s Office.

Mutual aid at the fire scene was provided by Fairfield and Norwalk firefighters, while station coverage was supplemented by firefighters from Norwalk and Wilton.