The fortuitous location of a water line prevented the displacement and potential injury of dozens of people on Sunday night, Chief Chris Switala of the Butler Fire Department said.

According to Switala, crews were dispatched at 11:11 p.m. to a large apartment building on West North Street across from Broad Street Elementary School for a fire in the basement.

Switala said upon arrival, firefighters noticed light smoke coming from the windows in a basement apartment unit.

They found the source of the smoke, which was a small fire inside a closet.

Switala said a water pipe inside the closet had extinguished the fire when the heat from the flames melted the solder on the pipe, causing the water to leak onto the fire and put it out.

Firefighters from Butler and the Veterans Administration Fire Department confirmed the fire was out and set up ventilation to remove the smoke from the building.

While the apartment building has tenants, the basement apartment unit where the fire occurred was unoccupied, Switala said.

About 30 people were evacuated from the building, and began to be let back inside after about 1.5 hours, he said.

All tenants were able to return to their apartments within a few hours.

“The fire damage was contained to the closet in the basement unit,” Switala said.

He said the person who called 911 to report the fire told dispatchers they heard an explosion as well.

“No explosion occurred,” Switala said. “It was probably just a noise as the fire progressed.”

He estimated damages at about $5,000.