A small electrical fire at an Alexandria high-rise apartment building triggered a massive fire department response Wednesday evening, forcing several Old Town streets to be shut down, city officials said.

Firefighters responded to a 22-story building in the 400 block of Madison Street, in the north end of Old Town, where a transformer caught fire about 6 p.m., said Brian Hricik, the city’s Emergency Medical Services Operations manager. The fire was isolated to a maintenance area on a lower floor near the building’s garage, but it produced smoky and hazy conditions in those areas.

No injuries were reported. The two-alarm response brought about 50 firefighters and paramedics responded to the scene, but most residents were able to shelter in place.

The fire was extinguished quickly once officials shut off electrical power to the entire building.

Officials do not expect any residents to be forced from their homes.

The city shut down the 400 and 500 blocks of Madison Street and Pitt Street between Madison and Wythe streets, Hricik said.

The cause of the fire remains under investigation.