EL PASO, Texas (Border Report) — Several alleged members of a drug trafficking organization known as “La Linea” have been arrested in connection with the Nov. 4 killing of nine Americans in Sonora, Mexico.

According to a news release issued Monday by the Mexican Attorney General’s Office, seven men are now being held on federal organized crime charges linked to the murders of three women and six children associated with the LeBaron Mormon colony in northwest Chihuahua state.

The federales only identified three of the detainees by name: Fidel and Juan Carlos “V,” and Javier “C.” They say four other people remain in custody but won’t identify them “for secrecy reasons” until they are formally arraigned. Fidel and Juan Carlos V., as well as Javier C. were arrested on Dec. 26 and later taken to a judge in Mexico City who found cause to link them to the murder case, the Attorney General’s Office said.

Relatives of two detainees have identified them as Hector Mario and Luis Manuel Hernandez, two brothers from the town of Janos, 70 miles west of Juarez, Mexico. The Mayor of Janos further identified his own police chief, Fidel Alejandro Villegas, as a suspect in the case. Villegas was arrested on Christmas Eve in Juarez. It’s unknown who the seventh suspect is.

Authorities have identified the adult victims as Dawna Langford, 43, Rhonita Miller, 30, and Christina Marie Langford Johnson, 29. The child victims range in age from 8 months to 12 years.

The killings, which sparked international outrage and prompted a joint Mexico-FBI investigation, are being attributed to a territorial spat between two rival Mexican drug-trafficking groups.

La Linea and a Sinaloa cartel proxy known as “Los Salazar” are vying for control of drug routes into the United States located along the Chihuahua-Sinaloa border.

La Linea, which operates in Chihuahua, had reportedly been involved in gun battles with Los Salazar days, if not hours, prior to the Nov. 4 killings. One of the groups allegedly mistook the three vehicles driven by the women as those of the rival group and opened fire with automatic weapons.

A federal official in Mexico City said earlier that it was La Linea who attacked the women’s vehicles.

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