More than 24 hours after several small explosions in Pepco’s underground equipment broke out windows in several buildings in the Logan Circle neighborhood of D.C., a company spokeswoman said the utility it did not know what caused the blasts.

Spokeswoman Mary Beth Hutchinson saidSunday afternoon that Pepco still was investigating what caused three or four explosions that occurred at about 1 p.m. Saturday near 13th and T streets NW, adding that it would be a while before damaged equipment could be fixed.