Officials in Mexico say they have made arrests in the murder of nine U.S. citizens by suspected cartel gunmen in the northern part of the country.

Officials are not saying how many people have been arrested, or if they have ties to drug cartels.

Nine women and children were killed last Monday in the ambush attack by suspected cartel gunmen in the Mexican state of Sonora.

The victims were dual U.S.-Mexican citizens and members of Mormon communities in northern Mexico not affiliated with The Church of Jesus Christ of Latter-Day Saints.