9 U.S. citizens, including 6 children, killed in shooting attack by Mexican cartel

At least three women and six children, all U.S. citizens, have been murdered by drug cartel gunmen in northern Mexico.
The tragedy happened on Monday when members of the LeBaron family, dual Mexican and American citizens, were ambushed while traveling in three separate SUVs in the Mexican border state of Sonora.
Mexico's security secretary said the gunmen may have mistaken the group's large vehicles for those of rival gangs.
Police say they are attempting to track down the killers.