Four people, including a district chief, have been killed by a roadside bomb in a region of northern Afghanistan that has been largely peaceful until now, AP quoted an Afghan official as saying. Senatullah Tumor, the spokesman for the governor of northern Takhar province, said Sunday that the bomb killed Hamidullah Haqjo Ashkamesh, chief of the Ishkashim district, as well as a police officer and two of his bodyguards. The Taliban claimed responsibility for the attack.