A fire tore through a popular south suburban restaurant early Friday, authorities said, decimating the historic building just days before the business was slated to host an annual barbecue festival.

At around 2:43 a.m., firefighters were called to the Maple Tree Inn, located in the 13300 block of Olde Western Avenue in Blue Island, according to Blue Island Fire Chief Dan Reda.

Upon arrival, crews discovered flames in every part of the two-and-a-half story building, which is over 100 years old, he said.

All of the building’s residents, including the restaurant owners who live upstairs, were able to safely evacuate the building, according to Reda.

“The owners reported they heard a pop a little before that,” Reda said. “Their detectors started going off, which is a good thing. They made their way to the back of the building and saw fire throughout so they exited the building safely.”

The crews worked for hours to knock down the bulk of the fire, officials said, though a gas line ruptured, feeding portions of the flames and presenting a difficult challenge for firefighters.

Around 20 fire departments responded to the scene, Reda said, and were awaiting the arrival of Nicor Gas to dig up the street to shut off the gas.

Two firefighters sustained minor injuries in the effort, according to fire officials: one suffered a laceration to his hand and was treated at the scene, while another was taken MetroSouth Medical Center with a lower back injury, Reda said.

“We had a lot of fire on arrival,” Reda said. “The crews did a good job of getting the bulk of it knocked down but with these older buildings, they’ve been chasing it for most of the morning.”

“It’s labor intensive,” he added. “It’s getting people in the building, opening it up and just chasing it.”

The Maple Tree Inn has been in the community since 1975, its website says, a second-generation, family-owned business. The building was built in 1890, with restaurant employees saying it was an old speakeasy during the Prohibition era, complete with tin ceilings and an old bar.

“It’s a staple in Blue Island,” Reda said. “It’s been here forever. Obviously it’s a shame to see any business, any resident have a fire like this – and they were actually preparing for a large event this coming weekend.”

The restaurant's website featured an advertisement for the “Barbeque, Brews and Bluegrass Festival” on Sunday, featuring an all-you-can-eat menu, craft beer tent and live music. It wasn't immediately clear if the event would still take place.

"It’s like a nightmare, I just wish I could wake up from it," Maple Tree Inn chef Tom Hecht said at the scene with tears in his eyes. "It's devastating. That's the only word I can think of, it's just devastating."

The cause of the fire was still under investigation, officials said, and crews remained on the scene.