QUETTA - Afghan forces closed border at Chaman on Saturday that suspended supplies to American and NATO forces in Afghanistan. Chaman border is the second important route after Torkham for supplies to American and NATO forces. Besides it, this route is also important for trade between Pakistan and Afghanistan. Sources said personnel of Frontier Corps had stopped some vehicles carrying grapes, watermelons and other fruits from Afghanistan for checking purposes because Afghan border areas are a major source of smuggling of narcotics and illegal arms into Pakistan. They said the delay caused by checking infuriated Afghan forces and they closed the border in retaliation. Because of closure of the border hundreds of vehicles were stranded on both sides. The situation also created serious difficulties for the people who wanted to cross the border on both sides. Meanwhile, four people including three security personnel were injured in two different landmine explosions in Chamalang area on Saturday. As per reports reaching here, four people including three security personnel were wounded when two landmines laid by unknown militants exploded with a big bang. The injured were shifted to a hospital for treatment where condition of the three was stated to be serious. The injured were identified as Syed Muhammad, Jano, Bakhsh and Deno. Police registered a case and started investigation.