A suicide bomber targeting a U.S. military convoy detonated a motorbike packed with explosives outside a boys' high school in eastern Afghanistan Monday killing at least 10 students, and two American soldiers.<br/> <br />About 20 people were wounded in the attack -- most were schoolchildren<br/> <br />Concerns are mounting over how Afghan security forces will cope with an intensifying insurgency once most foreign troops leave by the end of next year.<br/> <br />Western officials say the insurgency is responsible for about 86 per cent of all civilian casualties - or about 1,500 people - across the country this year.
