A suicide attacker detonated his explosive-laden car at a roadside security post in northwestern Pakistan on Monday, killing four troops and wounding eight others, officials said. The paramilitary post was targeted on the outskirts of Thal, a town in the North West Frontier Province, a police officer said on condition of anonymity because he did not have the authority to speak to the media. The army's top spokesman Maj. Gen. Waheed Arshad confirmed the bombing but said he did not have any immediate confirmation of casualties.