A 12-year-old suicide bomber has killed four people and wounded a dozen in east Afghanistan as the Taliban's threatened spring offensive got under way. Rebel clashes with police and Nato-led troops also left five civilians and two police dead. The death toll from the day's fighting included at least three children besides the bomber, and dozens of civilians were wounded in firefights. The boy detonated an explosive vest in a marketplace in Paktika province near the Pakistan border, provincial spokesman Mukhlis Afghan said. "The head of Shkin district council, Shair Nawaz, a woman and two other men were killed and...