A bomb attack in a restive Pakistani tribal area on Wednesday destroyed a tanker carrying fuel for Nato forces in Afghanistan, officials said. The bomb planted under the oil tanker exploded near Parangsum village in the lawless Khyber tribal district, turning the vehicle into a huge ball of flame, administration official Shafirullah Wazir said. There were no casualties. The bomb was fixed to the tail end of the tanker with a magnet and the explosion burnt some 40,000 litres (8,800 gallons) of fuel it was carrying for Nato forces in Afghanistan, Wazir told AFP. Another Khyber administration official confirmed the incident, saying there were no casualties and blamed the attack on the militant group Lashkar-e-Islam. Khyber is on the main Nato land and supply route through Pakistan into Afghanistan, where more than 121,000 foreign forces are battling to reverse an escalating Taliban insurgency, now into its ninth year.