By Kathy Gannon & Kay Johnson, Associated Press, May 16, 2013
KABUL, Afghanistan -- A suicide car bombing tore through a U.S. convoy in Kabul on Thursday, killing at least 15 people including six Americans in a blast so powerful it rattled the other side of the Afghan capital. U.S. soldiers rushed to help, some wearing only T-shirts or shorts under their body armor.
A Muslim militant group claimed responsibility for the morning rush hour attack, saying it was carried out by a new suicide unit formed in response to reports that the U.S. plans to keep bases and troops in Afghanistan even after the 2014 deadline for the end of the foreign combat mission.
The group, Hizb-e-Islami, said its fighters had...