PHILADELPHIA (CBS) — Crews battled a huge early morning fire at a bar and restaurant undergoing construction in Center City that left forced hundreds of residents from their homes.

Flames broke out around 4:30 a.m. Tuesday inside the two-story building at 13th and Chancellor Streets and quickly grew to three alarms.

“Little explosions started happening,” said one neighbor. “The fire just grew so fast. It was huge within minutes.”

Liz Morel adds, “I saw the sparks and smelled the smoke. I’m just so thankful I was able to get out.”

Residents of the adjoining Gramercy and Chancellor apartment buildings were evacuated. Both buildings sustained minor damage.

“I ran outside. I don’t even have shoes on or a jacket or anything,” said one woman who lives on 11th floor of Chancellor Apartments. “I knew enough not to try to grab any possessions, because it was that furious.”

One hundred firefighters from 20 companies worked to get the fire under control in less than two hours.

No one was injured in the blaze.

“The alarm systems worked in both buildings, which is a good thing,” said Fire Commissioner Derrick Sawyer, “and we got everyone out in a timely manner.”

Some of the residents were allowed to return to their apartments after several hours. Others were expected to be displaced for the day or possibly longer.

The fire caused several road closures and bus detours around the scene.

There was no immediate word on what sparked the blaze.

The ATF was investigating along with the Philadelphia Fire Department.