The killing of nine U.S. citizens—six children and three women—from a Mormon community in northern Mexico has caused outrage on both sides of the border.

Five other children were wounded, according to the U.S. State Department, and were taken across the border in Phoenix, Ariz.

Mexican officials say a drug cartel was behind the attack, though it’s not clear whether the family members were the intended targets or the victims of mistaken identity.

Here’s what we know so far about the attack.

What do we know about the attack?

HO/AFP via Getty ImagesTV grab from a video published by Lebaron’s family on social media showing a burnt vehicle that was carrying three women and six children from an American Mormon family near Rancho de la Mora, in the boundaries of Sonora and Chihuahua states, northern Mexico, on Nov. 4, 2019.

The women and children—who were U.S. citizens—were traveling from Bavispe in the state of Sonora, Mexico—about 70 miles south of Douglas, Ariz.— to Janos, Chihuahua on Monday night in two separate vehicles. In a mountain range at the state line, authorities say they were ambushed by attackers who opened fire on their vehicles and set them on fire.

Video shared on Facebook shows one of the SUVs riddled with bullet holes and still smoldering. A man’s voice can be heard saying, “This is for the record. Nita and four of my grandchildren are burnt and shot up.”

A relative of the family named Julián LeBarón contacted the Mexican national guard for help, according to Mexico’s Security Secretary Alfonso Durazo. The national guard was deployed from the nearby towns of Janos, Moctezuma and Casas Grandes to search for survivors, according to Durazo.

Relatives shared on Facebook that at least one of the children attempted to walk back to town to find help after hiding his injured siblings in bushes.

Six children survived, according to Mexican authorities. Five of the children were in stable condition at a hospital in Phoenix. One child is being treated for a bullet wound to the back.

Mexican President Andrés Manuel López Obrador told reporters that the attack happened at 1:30 a.m. on Tuesday. The authorities said that the attackers might have misidentified the vehicle as belonging to a rival cartel, but Obrador added it is too soon in the investigation to be certain.

The region has a long history of cartel violence and many have been attacked there, Obrador said, including a police chief who was shot and killed more than a decade ago.

What do we know about the victims?

The victims were reportedly members of an offshoot of The Church of Jesus Christ of Latter-day Saints.

Jhon LeBaron, who said he was related to the victims, wrote in a Facebook post, “On the morning of November 4th, 2019, three mothers in three vehicles, with fourteen children between them, set out from LaMora, a small family community in the mountains of northeastern Sonora… We lost 9 today. Right now we are waiting, for the morning, for answers, for justice.”

They have not been named officially, though family members have posted pictures of the dead on Facebook and identified them.

They are three women age 29, 30 and 43; and six children including 8-month-old twins; two boys, ages 2 and 12; and two girls, ages 10 and 11.

LeBaron also identified the survivors as ranging in age from 7 months to 14 years old.

At least one GoFundMe account has been set up by a friend of one of the victims. It has raised close to $40,000 as of Tuesday afternoon.

How has the Mexican government responded?

Sashenka Gutierrez—EPA-EFE/Shutterstock Mexican President Andres Manuel Lopez Obrador (L) and Security Secretary Alfonso Durazo (R), participate in a morning news conference on the attack, in Mexico Cit on Nov. 5, 2019.

The Mexican president told reporters Tuesday that, “Violence cannot be met with violence,” and urged for peace instead of retaliatory attacks.

#ConferenciaPresidente | Martes 5 de noviembre de 2019 https://t.co/PlXcYGDrur

— Gobierno de México (@GobiernoMX) November 5, 2019

Sonora Gov. Claudia Pavlovich Arellano said on Twitter that her office would be collaborating with authorities to ensure those responsible are found.

“As a mother, I feel anger,” she said. “And a profound pain for the cowardly acts committed in the mountain range between Sonora and Chihuahua. I don’t know what kind of monster could hurt women and children.”

Como madre siento coraje, repudio y un profundo dolor por los cobardes hechos en la sierra entre Sonora y Chihuahua. No sé qué clase de monstruos se atreven a lastimar a mujeres y niños. Como Gobernadora toda mi colaboración para que no quede impune y paguen los responsables.

— Claudia Pavlovich A. (@ClaudiaPavlovic) November 5, 2019

César Peniche Espejel Attorney General for the Mexican state of Chihuahua said in a statement that the agency has deployed resources to help in investigation and has been in touch with at least one family member.

Mexican authorities have recently been struggling to contain cartel violence. In October, authorities botched the arrest of Ovidio Guzmán, the son of Joaquin “El Chapo” Guzmán, when hundreds of gunmen attacked security forces in Culiacán where Ovidio was held.

How has the U.S. government responded?

President Donald Trump tweeted about the attack Tuesday morning, “A wonderful family and friends from Utah got caught between two vicious drug cartels, who were shooting at each other, with the result being many great American people killed, including young children, and some missing.”

“The great new President of Mexico has made this a big issue, but the cartels have become so large and powerful that you sometimes need an army to defeat an army!” Trump continued.

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. We merely await a call from your great new president!

— Donald J. Trump (@realDonaldTrump) November 5, 2019

….monsters, the United States stands ready, willing & able to get involved and do the job quickly and effectively. The great new President of Mexico has made this a big issue, but the cartels have become so large and powerful that you sometimes need an army to defeat an army!

— Donald J. Trump (@realDonaldTrump) November 5, 2019

“I haven’t seen President Trump’s message, but I’m sure the contents of it have to do with cooperation and aren’t disrespectful,” Obrador said on Tuesday.

“In the President’s Nov. 5, 2019, phone call with President Lopez Obrador, the leaders agreed that the United States and Mexico will cooperate closely with Mexico to ensure the perpetrators face justice. For example, the FBI has offered assistance to the Mexican authorities,” a State Department spokesperson said in a statement.

U.S. Ambassador to Mexico Christopher Landau tweeted in Spanish that “the safety of our fellow citizens is our top priority. I am closely following the situation in the mountain range between Sonora and Chihuahua.”

La seguridad de nuestros connacionales es nuestra gran prioridad. Estoy siguiendo muy de cerca la situación en la sierra entre Sonora y Chihuahua.

— Embajador Christopher Landau (@USAmbMex) November 5, 2019

“We offer our sincerest condolences to the families on their loss. We are closely monitoring local Mexican authorities’ investigation, and as President Trump and [Secretary of State Mike] Pompeo have stated, we offer to support this investigation,” the State Department spokesperson’s statement continued.

The State Department classifies Mexico as a Level Two travel advisory, and Sonora, the region of Mexico where the attack occurred, as Level Three, suggesting Americans reconsider traveling to the area.

Per the State Department’s website, “Sonora is a key location used by the international drug trade and human trafficking networks. However, northern Sonora experiences much lower levels of crime than cities closer to Sinaloa and other parts of Mexico.”

What is the history of Mormonism in Mexico?

The Church of Jesus Christ of Latter-Day Saints first began sending Mormon missionaries into Mexico into the 1870s, but Mormon colonization in Mexico began in the 1880s during the height of the U.S. government’s crackdown on polygamy, W. Paul Reeve, a professor of Mormon Studies at the University of Utah, tells TIME.

“You had federal marshals scouring Utah territory and over 1,000 men and some women who were sent to prison for practicing polygamy,” he says. So church leadership began to look for places of refuge across U.S. borders.

Some Mormon polygamists moved into northern Mexico, and some moved into southern Canada in the 1880s. They established “some fairly thriving communities in northern Mexico,” Reeve said, but they were upended by the Mexican Revolution of 1910.

During the Mexican Revolution there was substantial anti-American sentiment, and the Mormons who had moved there were seen by many as more American than Mexican. “By 1912 they were violently driven from their homes and returned back into the United States,” Reeve explains.

Most of those Mormons stayed in the U.S. after the revolution ended, but some returned to Mexico.

Reeve points out that at this point the Church of Jesus Christ of Latter-Day Saints officially abandoned the practice of polygomy long ago. In 1904, Joseph F. Smith announced that any member of the church who practiced polgomy would be excommunicated.

Some fundamentalist groups then moved back to Mexico, continuing to practice polygomy into the present, Reeve says. But many members of these colonies stopped performing plural marriages over the years, Matthew Bowman, a professor of Mormon Studies at Claremont Graduate University, adds.

Mexico is also home to many members of the Church of Jesus Christ of Latter-Day Saints. According to the church’s website, Mexico contains 1,455,744 members of the Utah-based church with nearly 2,000 congregations.

Original Article