QUETTA: Policemen guarding coal trucks survived a powerful bomb blast in the Mandaytak area of Duki district while Kharan town was rocked with two blasts on Friday night. Officials said that a police contingent was protecting trucks carrying coal for Punjab from Duki coal-mine field. They said that when trucks reached Man­da­ytak area, an improvised explosive device, planted by unknown people at a roadside, exploded, but it caused no injuries because it exploded when the vehicles had crossed the area. “No casualty took place in the blast,” police officials said, adding that a search operation has been launched in the area to trace elements who were behind the attack. Meanwhile, the Kharan town, the divisional headquarters of Rakhshan div­ision, was rocked at night when two explosions took place near an under-construction treasury office. Police officials said that unknown motorcyclists hurled two hand grenades with small intervals at an under-construction building which exploded, rocking the entire town. Police rushed to the area of the blast and started an investigation into the matter. “No casualty was report­­ed in both the explosions,” a senior police officer told . How­ever, the under-construction building was damaged.