BUFFALO, NY - Two On Your Side was at the scene of an underground electrical fire on Tupper Street near Pearl Street in downtown Buffalo Sunday afternoon.

The fire was reported about 11:30 a.m. when witnesses said they saw smoke pouring out of manholes. Buffalo Police closed off the intersection and were keeping people away from the scene. Two buildings had to be evacuated.

Two On Your Side photojournalist Dave Harrington said he heard an explosion as he was arriving. Then, while he was interviewing a witness, a second explosion sent a manhole cover soaring into the air.

A Buffalo Fire Department official confirms there was a third, smaller explosion at about 2 p.m.

National Grid cut off power to the immediate area around the fire. At about 2:30 p.m., firefighters told us the situation was under control, and they terminated their command post at the scene.

A National Grid crew remained on site. A spokesman for the utility told us the cause of the fire is still under investigation. They won't know until they are able to pull up the cable that burned, and that could be a few days.

The explosions were probably caused by the rapid build-up of heat, gas and smoke leading to intense pressure in the confined space under the road. The sequence of explosions moving along the street shows the fire was probably following a conduit.

The spokesman said to expect little to no traffic disruption for Monday morning's commute.

Tupper Street was closed between Delaware Avenue and Main Street for several hours.