3 mothers, 6 children slaughtered; Romney says Mexico must 'knuckle down and go after' cartels in wake of massacre

"It’s moms and children. This is really unthinkable. Mexico has to go after some of these cartels and stop this escalating level of violence,” the Utah Republican told reporters in Washington.

Romney said he doesn’t know a motive for the killings but would be surprised if the families were targeted. He said he thinks it’s much more likely “something associated with the business of the cartels,” adding no one will know until an investigation is done.

In a Senate hearing Tuesday, FBI Director Christopher Wray said the agency has reached out to Mexican authorities to help investigate. He said he also intends to have the FBI’s Victim Services Division offer assistance to family members in the United States.

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