Three Afghan civilians were killed by a land mine explosion on Wednesday near the same spot where a U.S. soldier died and four others were wounded hours earlier in a similar blast. The U.S. soldiers, part of military police contingent in western Afghanistan, were on patrol on a road near Shindand, site of a former Soviet air base close to the Iranian border, U.S. military spokesman Major Steve Wollman said. Three hours later a vehicle hit a land mine on the same stretch of road, killing three and wounding four Afghan civilians on board, Mohammadullah Afzali, a spokesman for the governor of Herat province told Reuters.