Officials confirm 3 women, 6 children have been murdered in a northern Mexico attack; relatives say all of the victims were US citizens.

Mexico's top security official says at least 3 women and 6 children were slaughtered by cartel gunmen and one child is still missing in northern Mexico. Relatives say the victims are U.S. citizens.

Security Secretary Alfonso Durazo says the gunmen may have mistaken the group's large SUVs for rival gangs. He said six children were wounded in the attack, and five have been transferred to hospitals in Phoenix, Arizona.

Durazo said the Sinaloa cartel has an important presence in the area, but is fighting for the territory with rivals.

The chilling attack targeted U.S. citizens who live in a community founded as part of an offshoot of The Church of Jesus Christ of Latter-day Saints.

Police and army troops are searching for a missing child.

As many as 13 other members of La Mora—a decades-old settlement in Sonora state founded as part of an offshoot of the Church of Jesus Christ of Latter-day Saints—were missing after the attack on a convoy of three SUVs carrying community members, said a relative of the family.