The attack began on Monday afternoon on a highway running parallel to the U.S. border as the three women and 14 children were travelling from the La Mora ranch in Sonora to Janos, Chihuahua.
The communities date back to a time when the US government was cracking down on polygamy in Utah in the early 1880s, prompting Mormon leaders to send pioneer families to establish colonies of "true believers" in Canada and Mexico, according to Jon Krakauer, who detailed the history of the fundamentalist communities in his book "Under the Banner of Heaven". In the bullet-riddled hulk of one SUV, the men found a a 7-month-old baby girl, still alive and strapped in her vehicle seat, on the floor, where her mother had apparently tried to hide her, LeBaron said.
Dawna Langford - Devin's mother - had been driving one of two SUVs headed to meet family in Chihuahua when the gunfire broke out.
State and federal authorities are investigating the incident, authorities said. Dawna and two sons were killed.
The killers were apparently members of the Juarez drug cartel and its armed wing, La Linea - The Line - whose gunmen had entered Sinaloa cartel territory and set up an armed outpost on a hilltop and an ambush further up the road.
After the attack, with no surviving adults and the oldest sibling shot in the foot, 13-year-old Devin Langford, whose mother, Dawna, and two other siblings were killed in the attack, had to walk for about 14 miles to La Mora, where the family lived, to look for help.Before setting off, Miller said Devin had to hide his wounded siblings in the bushes, covering them with branches.His sister, Mckenzie Langford, 9, was grazed in the arm with a bullet, but she also went to look for help after Devin did not come back, Miller said.
President Trump tweeted a condemnation of the attack and said "This is the time for Mexico, with the help of the United States, to wage WAR on the drug cartels and wipe them off the face of the earth".
Mexican officials said extra federal and local security forces have been deployed.
The account was posted on social media by relative Kendra Lee Miller, who said when he took too long to return to his six siblings, his six-year-old sister Mckenzie Rayne Langford left the others to try to get help.
"That's one of the most relevant details we can give you", he told reporters at a news conference on Wednesday.
For 11 hours, relatives had no idea about what had happened to their loved ones.
The youngest of Devin's siblings, 9-month old Oliver, was shot in the chest; 8-year-old Cody had bullet wounds to the jaw and the leg, while Xander, 4, had been hit in the back. Search parties later found her, the families said.
The older woman, 14-year-old Kylie Evelyn Langford, was shot within the foot, Liddiard mentioned.
The dead included two 8-month-old twins and a toddler, relatives said. While he was gone, Devin's nine-year-old sister, McKenzie, had anxious that her brother had been away too long, so she went for help. Staddon said her brother discovered the bullet-ridden vehicle that was still smoldering, and shot video of the charred bodies inside as evidence.