(CNN) All that was left for family members to sift through when they arrived at the scene of a massacre in Mexico on Monday were ash, bones and a car -- ablaze and riddled with bullet holes.

Just that morning, they hadseen the three women and their 14 children off to visit family, traveling together for safety. Now, loved ones and investigators are piecing together what happened in the remote mountains where the women and six of their children were killed.

The dual US-Mexican citizens were drivingthrough a remote area in the mountains on the border between the Mexican states of Sonora and Chihuahua. They had left the La Mora community, which appears to be a group of fundamentalist Mormons separate from the mainstream Church of Latter-day Saints . One journeyed to pick up her husband, another to meet her husband and move to North Dakota and the third to visit family in the neighboring state of Chihuahua, relative Kendra Lee Miller said.

The three had returned to the family ranch after one of their cars got a flat tire and set off on their way again, Miller said. Miller's brother was fixing the flat when he saw an explosion and rushed to the scene.

The family, their community, the Mexican government and the US government are now all working to understand what happened to the family and why. Here is what happened based on the accounts of the Mexican Security Minister Alfonso Durazo and a commission ordered by Mexican President Andrés Manuel López Obrador to investigate the attack:

9:40 a.m. local time Monday: The first vehicle carrying Rhonita Miller and her four children, aged 12, 10 and 8-month-old twins, was ambushed, the Investigative Commission said Wednesday. None of the passengers survived. Durazo's account states that the families began their journey around this time.

11 a.m.: The second and third vehicles were attacked, the commission said. One was driven by Dawna Ray Langford. Of the nine children she had with her, two were fatally shot along with her. The third vehicle was driven by Christina Marie Langford Johnson, who had her infant daughter in the car. The baby survived, but Christina did not. Durazo disputes this timing, saying that the families were ambushed at 1:00 p.m. local time.

1:18 p.m.: Durazo said a family member, Julián LeBarón, alerted the National Guard about the attack and requested support.

6 or 7 p.m.: Search efforts begin for the children who survived. Durazo's account sets this an hour earlier than the commission's.

8:30 p.m.: The commission says that five surviving children were given first aid. About 15 minutes later, the commission says they were taken to a hospital in Bavispe, Mexico. The infant was found in her car seat on the floor of her mother's car surrounded by bullets but uninjured, Kendra Lee Miller said. The five children had been hidden in nearby bushes by their 13-year-old brother, who had The commission says that five surviving children were given first aid. About 15 minutes later, the commission says they were taken to a hospital in Bavispe, Mexico. The infant was found in her car seat on the floor of her mother's car surrounded by bullets but uninjured, Kendra Lee Miller said. The five children had been hidden in nearby bushes by their 13-year-old brother, who had walked about six hours back to the family ranch, she said. One of their sisters was not with them.

9:45 p.m.: The last surviving child -- a missing girl -- is found, the commission said. Miller said the 9-year-old had left to find help. Another family member said they found her with The last surviving child -- a missing girl -- is found, the commission said. Miller said the 9-year-old had left to find help. Another family member said they found her with her feet swollen and covered in blisters from walking.

11:40 p.m.: Air transportation takes five of the children and two family members to a Red Cross ambulance in Agua Prieta, the commission said.

12:05 a.m. Tuesday: The Secretary of National Defense confirmed the deaths of three women and six minors, Durazo said.

12:30 a.m.: Those transported arrive in the US for care, the commission said.

Mistaken identity or targeted attack?

Officials and family members have been at odds over whether this was a case of a cartel mistaking them for a rival or if the family was a target.

Kendra Lee Miller, who lost her sister-in-law in the attack, said "cartels have taken too many of our family members."

She said cartels had recently threatened her family over where they can travel.

"They had stood up to the drug cartels, and they did have certain frictions either with the cartels or with neighboring communities over water rights," Former Mexican Foreign Minister Jorge Castañeda said.

But Lafe Langford disputed Castañeda's description of his family.

"It's so far from the truth. The only thing they were activists for was their children, the education of their children and their homesteads," Langford said.

"(Castañeda) said something about a conflict over water rights. We live on a river. We have all the water we could ever need."

A suspect arrested, but manhunt continues

On Tuesday, Mexican authorities announced the arrest of a suspect in relation to the massacre. But Wednesday, Durazo said investigators have learned the suspect was not involved.

Authorities did not say whether the individual has been released.

While the investigation unfolds, authorities in the US and Mexico have different theories on who might be responsible.

Chihuahua Attorney General César Peniche Espejel said he believes the newly formed Los Jaguares cartel, an offshoot of the infamous Sinaloa drug cartel, may be behind the massacre.

"These very cartels of Sinaloa, after the arrest of Guzman 'El Chapo,' have suffered fragmentations," Peniche Espejel said.

But a US official said Tuesday that a rival cartel called La Línea is under scrutiny.