(Xinhua) -- A blast killed five civilians and injured five others in Paktia province of eastern Afghanistan on Saturday, the private TOLO TV reported. The civilians were collecting firewood in the mountain when the explosion happened, it said. TOLO did not mention that the explosion was caused by an old mine or a newly planted bomb. Numerous mines are still being buried in many corners of this country due to decades of war, causing heavy casualties every year, while militants have frequently planted bombs to attack government and foreign forces. Meanwhile, Zemarai Bashary, spokesman for the Afghan Interior Ministry, told Xinhua he had no information about the explosion, but would contact provincial officials to check it. On Wednesday, an old mortar shell killed one scavenger boy and wounded another on the outskirts of southwestern Kabul.