Springfield, MA – Carbon monoxide fumes from a worker using a gasoline-powered saw indoors prompted the emergency evacuation of an Allen Street strip mall Wednesday afternoon.

The Fire Department was initially summoned to 1504 Allen St. for a report of a natural gas leak shortly before 1 p.m., said Dennis Leger, aide to Commissioner Joseph Conant. Firefighters determined, however, that the odor was caused by carbon monoxide — several hundred parts-per-million — and not natural gas.

“Someone was running a gasoline-powered saw inside the building in the back,” Leger said.

A number of businesses and operations were evacuated, including Open Arms Child Care Center and Thom Springfield Toddler Infant Services. Some 50 to 60 people were evacuated in all, Leger said.

Leger said those evacuated will be allowed back inside once the building has a chance to air out.

It’s dangerous to run such equipment inside, Leger said. “We don’t recommend running gasoline-powered anything inside,” he said.