Police in Afghanistan say a suicide car bomber has attacked near a U.S. base in eastern Afghanistan. There was no immediate report on casualties. Youqib Khan, the deputy police chief in Khost province, said the attack Sunday happened in the city of Khost near Camp Chapman, which still houses U.S. forces. Khan says foreign troops have blocked off all access to the area where the attack happened. NATO says it was aware of an “explosion” in Khost, without elaborating. U.S. officials could not be immediately reached for comment.