Georgia ? Crews were waiting for an area to cool off under the streets of downtown Savannah before they could start determining what caused an electrical explosion Monday that blew off manhole covers and knocked out power for hours to many stores, restaurants and homes.

By late Monday, almost all streets had reopened, as did stores and restaurants evacuated after the blast, said police spokesman Gene Harley. Also, crews had restored power to all the homes and all but a few businesses that had gone dark, said a Georgia Power spokeswoman. No injuries were reported and there was only minimal property damage, officials said.