A ruptured underground gas line closed several lower peninsula streets for three hours or more on Wednesday, and left more than 400 homes and businesses without natural gas service over night.

The leak was discovered about 4 p.m. near the intersection of East Bay and Tradd streets. Charleston firefighters had the leak shut off by 7 p.m., when the scene was turned over to South Carolina Electric & Gas Co., fire department spokesman Mark Ruppel said.

SCE&G spokesman Robert Yanity in Columbia said 436 gas customers were without service late Thursday, and probably will not see it restorted at least until today. He said SCE&G was trying to contact every affected customer. Those customers are located mainly from Broad Street down to East Bay, over to South Battery and up to Meeting and Broad, Yanity said.

He said the cause of the leak was not known, and the work to repair or replace the broken line will require excavation. Traffic in the area will likely be affected, he said.

Shortly after the leak developed, police evacutaed some nearby buildlings and closed parts of East Bay, Tradd, Church, Concord, Logan and Broad streets, and Boyes Wharf. Detours were set up.