Taliban insurgents ambushed a U.S. security firm convoy in southwestern Afghanistan on Friday, killing four guards and four civilians, a provincial official said, the second attack on the firm in as many days. The convoy was passing through Bakwa district in Farah province when militants opened fire with heavy machine guns, setting alight four vehicles, the official said. Another convoy of the security firm was attacked on Thursday in Kandahar and two people were killed, Reuters reported.
