Stranded Pakistani truck drivers carrying fuel and other supplies to U.S.-led troops in Afghanistan said Sunday that they were exposed to attacks by Islamist militants, after Islamabad closed the country\'s border crossings in retaliation for coalition airstrikes that allegedly killed 24 Pakistani troops reported AP today.Suspected militants destroyed around 150 trucks and injured drivers and police a year ago after Pakistan closed one of its Afghan border crossings to NATO supplies for about 10 days in retaliation for a U.S. helicopter attack that accidentally killed two Pakistani soldiers.