A man who sold Civil War relics that included munitions was killed by an explosion, and residents of the neighborhood were kept out of their homes Tuesday as experts looked for more explosives.

Samuel H. White, 53, was found in his backyard Monday by neighbors who had heard the blast, Chesterfield County police said.

Police Capt. Steve Neal said that what exploded was military ordinance, possibly dating from the Civil War. Authorities found unexploded military ordnance at his house, and on Tuesday they were still collecting and detonating explosives.

White's business, Sam White Relics, advertised various relics for sale including Civil War artillery shells, cannon balls and bullets. His Web site says he "will disarm, clean, and preserve your Civil War period and earlier military ordinance" for about $35 each.

About two dozen nearby homes were evacuated as a precaution and police spokeswoman Ann Reid said the evacuation would remain in effect infinitely.

Neighbor Brian Dunkerly told the Richmond Times-Dispatch the explosion hurled a chunk of metal weighing close to 15 pounds that struck the roof of his front porch about a quarter mile from White's house. He said no one was hurt, although the piece of metal shattered his glass front door, hit the floor inside and bounced to the ceiling before coming to rest in the center of his living room.