INDIANAPOLIS -- An underground explosion and fire along an Indianapolis street, the second on the same street in two days, causing a power outage that shut down air conditioning at the City-County Building.

The explosion happened at about 9:45 a.m. in the 300 block of Massachusetts Avenue.

The blast was blamed on an electrical transformer.

Wednesday's blast happened in the same general area, right in front of Indianapolis Fire Department headquarters.

Witnesses in Wednesday's incident said they heard a loud boom, then saw flames reaching 25 feet into the air from a manhole.

No injuries were reported in either incident and there was no permanent damage. Power was out to one building nearby, and the CCB lost its air conditioning.

Fire officials think older lines are to blame for the explosions, and Indianapolis Power and Light confirmed a problem with underground lines in the area.

Power was restored to all affected by 3 p.m., IPL officials said.