Georgia Power is investigating what caused several manhole explosions in downtown Atlanta on Monday night.
The blasts shut down Peachtree Street between Mitchell and Alabama, and Martin Luther King Jr. Boulevard between Pryor and Spring streets.
Some people told Channel 2's Amy Napier Viteri they thought a bomb was going off.
Police reopened most of the roads by late Monday night but Georgia Power crews were still working on Broad Street between Mitchell and MLK.
That's where they said an underground fire led to several manhole covers exploding out of the ground.
People downtown heard the explosion for blocks around 7 p.m. Monday.
"They said it's a fire up underground and it blew off the manhole," Desiree Bennett told Viteri. "There was fire and I could not believe. We could not believe what we saw."
Bennett took this cellphone video of the incident, which shows smoke coming up from the street after the first explosion on Broad Street.
She said just minutes later a second manhole cover blew, breaking it in half.
"It broke in two mid-air. So that was enough to tell me to leave," Bennett said.
Viteri said she saw Georgia Power crews at the corner of Broad Street examining one split manhole cover.
A representative said cables in an underground vault caught fire, which led to about five manhole covers blowing off. Crews cut off power to nearby buildings Tuesday morning so they can get into an underground vault to see what happened. Sources told Channel 2's Sophia Choi power is not expected to be returned until Tuesday afternoon.
Bennett said she talked with a bus driver who had just driven over one of the covers when it flew into the air.
"She said she looked in the side view mirror and saw the flames behind the bus. Luckily she wasn't over the manhole," Bennett said.
Power crews are working to learn how the cables caught fire inside the secured vault. Bennett, who lives in the area, left home for several hours Monday night and was nervous about returning.
"No one knows what happened so I'm very concerned, yes," Bennett told Viteri.
A Georgia Power representative said no one was hurt in the incident. They think as many as 10 buildings could have power outages, but they're closed commercial buildings.
It could be a day or two before crews know what caused this but right now the priority is making repairs to get power back on.