Baltimore firefighters scaled towering ladders to rescue two residents trapped on a burning patio as flames engulfed the eighth floor of a high-rise apartment building in downtown Thursday evening, officials said.

The two-alarm fire broke out at the 222 Saratoga apartment complex in the 200 block of E. Saratoga St. around 6:20 p.m., sending thick smoke billowing over the city.

Crews battled the blaze for over an hour, bringing it under control by 7:25 p.m., according to Baltimore Fire Department spokesman John Marsh.

Both rescued residents were treated for non-life-threatening injuries and taken to a nearby hospital. The American Red Cross of the National Capital and Greater Chesapeake Region said in a news release that they assisted 18 families after the fire on Thursday.

No firefighters were injured in the operation, and the cause of the fire remains under investigation.

The blaze prompted emergency road closures, with Baltimore City’s Department of Transportation urging drivers to avoid Saratoga Street, Guilford Avenue, Lexington Street and Calvert Street.

The area is home to several high-rise apartment buildings and the nearby Mercy Medical Center.