KHYBER AGENCY As many as eight Nato oil supply tankers were torched on Tuesday here in Torkham, political administration and Khasadar sources said. The sources said last evening a device installed by some unknown miscreants under one of the oil supply tankers exploded in Torkham parking hub. After the blast, the tanker caught fire and engulfed other seven tankers parked nearby, the sources told. The incidents of torching the tankers were likely to increase, said Torkham administration official. However, no casualty was reported. Fire brigade and political administration officials rushed to the spot to stop further loss, source told. Attacks on the Nato tankers have got momentum in the area and during the last month dozens of tankers have been reduced to ashes.