New York City residents living in midtown Manhattan were abruptly awakened Sunday morning by multiple manhole explosions that sparked fires and caused several power outages.

The FDNY received calls about the explosion on 56th Street around 4:30 a.m. ET, NBC New York reports. Firefighters were later joined by EMS and Con Edison crew members, who remained on the scene for hours.

“Units responded in about three or four minutes. They got on scene and found multiple manholes with smoke issuing from it,” John Sarrocco, the FDNY Deputy Assistant Chief, said in a statement.

“We did searches throughout all of the buildings on each side of the street, on 56th Street between First and Second Avenue. The situation seemed to be under control at that point.”

Although things appeared to settle down, another explosion at 7:40 a.m. injured three workers, one from each of the emergency services, amNY reports.

The blast left several hundred NYC residents in the area without electricity and customers shouldn’t expect to have power restored until early Monday.

The explosion required a three-alarm response and caused the release of carbon monoxide as well as damages to storefronts and vehicles nearby.

“We had multiple power outages on 56th Street between First and Second Avenue with rising CO levels in various buildings. We escalated the incident to have a second alarm assignment respond, which consists of approximately 200 firefighters,” Sarrocco stated.

“Those firefighters had to do extensive searches of buildings on 56th Street between First and Second. Checking all of the elevators because there are multiple power outages. We also have civilians that need electricity for life support systems.”

Although Con Edison suspects the recent snowstorms may be responsible for the manhole explosions, an investigation to determine what caused the ear-splitting blasts has been launched.

Pictured: New York City firefighters put out a fire in a midtown residential building in Manhattan in New York City, June 12, 2015. Getty Images/ Spencer Platt