Dramatic video shows adults and children jumping from a third-floor window to a balcony below to escape a fire engulfing the back of a Chicago apartment building.

The building on Chicago’s West Side caught fire at about 4 a.m., according to officials. Video taken by a bystander shows people jumping from a third-floor window to a second-floor balcony as smoke thickened inside and flames billowed from windows. Firefighters then used a ladder to rescue people from the second-floor balcony.

“There were people hanging out of that third-floor window on the front side of the building and a couple people started to hang jump out,” said 14th Battalion Chief Don Hroma of the Chicago Fire Department. “Smoke started to pump out of that window so they were probably starting to feel some heat from the fire below them and in the rear of the building.”

At least half a dozen people were rescued from the building, and everyone was accounted for as safe, Hroma said, according to NBC Chicago.

The fire was brought under control by about 5 a.m. The cause was not immediately known.