Nine U.S. citizens killed in drug cartel ambush in Mexico

Drug cartel gunmen ambushed three SUVs along a dirt road, slaughtering at least six children and three women - all of them U.S. citizens living in northern Mexico - in a grisly attack, authorities said Tuesday.

The dead included 8-month-old twins. Eight children were found alive after escaping from the vehicles and hiding in the brush, but at least five had bullet wounds or other injuries and were taken to Phoenix for treatment.

Mexican Security Secretary Alfonso Durazo said the attackers may have mistaken the group's large SUVs for those of rival gangs.

The attack took place in a remote, mountainous area where the Sinaloa cartel has been engaged in a turf war with another gang.