By Jericka Duncan and Andrew Kramer

LOWER PROVIDENCE TWP., Pa. (CBS) – Firefighters battled smoke and flames at a popular bar and restaurant in Audubon, Montgomery County Saturday afternoon.

Fire officials say the blaze started around 12:30 p.m. at the Valley Forge Beef & Ale located at 827 South Trooper Road in Lower Providence Township. They say the restaurant sustained heavy damage.

“I just look at a lot of time and energy to build a business and things happen,” owner Brian Flaxman said. His family owned the property for 40 years.

Over 100 firefighters from seven surrounding departments responded to the fire. It took four hours to bring the blaze under control.

Officials say 23 customers and employees were inside when the fire broke out and the building had to be evacuated. They believe the flames started somewhere in the basement of the restaurant.

“There was zero visibility in the basement area and the storage area for the restaurant, which impeded the initial firefighters from getting access to the fire,” Lower Providence Fire Chief Brian McFarland said.

Flaxman says he believes the restaurant’s basement gas heater caused the blaze.

No injuries were reported.