Gustavo Ángel Suárez Castillo, an American citizen from San Antonio, piled six pals, together with two brothers, into his white pickup truck with Texas plates simply earlier than daybreak, having spent the evening celebrating the information that he was going to be a father. All of a sudden, 4 automobiles crammed with armed males started chasing and firing at them.

The pickup truck crashed and because the passengers tumbled out, the armed males threw some to the bottom, taking pictures one within the again, survivors informed The New York Instances. One recounted how he watched his brother slowly cease respiration whereas the assailants blocked medics from arriving.

When it ended, 5 of the lads,  together with Mr.  Suárez, had been useless and the opposite two severely injured.

The attackers? Uniformed Mexican troopers.

The taking pictures within the metropolis of Nuevo Laredo within the early hours of Feb. 26 has been referred to as a coldblooded execution by the survivors and a prime authorities official. Thus far, 4 of the 21 troopers concerned within the encounter have been arrested and the case is underneath investigation by civilian prosecutors and the navy.

The episode has deepened considerations in regards to the rising footprint of Mexico’s armed forces, which has not solely been put in command of home safety, however has additionally been given a quickly increasing portfolio of companies, like a brand new worldwide airport and a significant rail line.

It underscores what human rights advocates and analysts say is a harmful flaw in Mexico’s governing system: one among the nation’s strongest establishment operates with little oversight.

Regardless of a lengthy historical past of human rights abuses, the navy assumed duty for civilian safety after the federal police was dissolved in 2019, taking up the nation’s violent prison organizations, but in addition placing residents vulnerable to changing into victims of heavy-handed ways, critics say.

The Protection Ministry is underneath the command of an active-duty basic, not a civilian chief, is just not required to publicly launch paperwork or report on its actions and infrequently refuses to look earlier than Mexico’s Congress to reply questions.

The navy’s strict management over its affairs has led the Mexican president to consolidate authorities tasks underneath the armed forces to restrict their transparency and has meant that instances of civilian deaths by the hands of the military nearly by no means go to trial.

“Given the growing position of the armed forces in Mexico, it’s actually essential and pressing” that they “are regulated with a civilian supervision mechanism, which must be created to manage and ultimately get accountability,” mentioned Marta Hurtado, a spokeswoman for the United Nations Excessive Commissioner for Human Rights.

The U.N. has referred to as for an impartial investigation into the Nuevo Laredo killings, citing the navy’s historical past of extreme use of drive within the metropolis.

An preliminary navy assertion implied that the lads within the pickup had been armed and had not heeded orders from troopers.

However that declare was contradicted by Alejandro Encinas, a prime federal authorities human rights official.

“It was not a confrontation,’’ Mr. Encinas mentioned. “They had been executed.”

The troopers fired 117 rounds in the course of the incident although the victims by no means brandished a weapon, a preliminary report by the Nationwide Fee on Human Rights discovered.

The Protection Ministry declined to touch upon the killings, citing the continuing investigations.

Requested for touch upon Mr. Suárez’s killing, an American official mentioned the U.S.  authorities had issued its highest-level warning for Tamaulipas, the state that features Nuevo Laredo, and had warned its residents to not journey there.

Legal professionals representing the households of the useless and the survivors say the military has tried to cowl up particulars of what unfolded that morning.

They accuse the troopers of eradicating the truck’s license plates to bolster their accusation that the lads had been behaving suspiciously. A survivor mentioned he was compelled at gunpoint to tape a confession that the lads had fired on the troopers first.

Per week after the assault, a few dozen troopers confirmed up round midnight at one of many survivor’s properties in an try to intimidate him into silence, his attorneys say.

“We don’t perceive why they shot some younger individuals who weren’t even attacking them,’’ mentioned Raymundo Ramos, the president of the Committee of Human Rights in Tamaulipas, an advocacy group representing the survivors and the households of the useless males.

(An earlier New York Instances investigation revealed that Mr. Ramos had been spied on illegally by the navy whereas engaged on a special case in Nuevo Laredo involving the armed forces and accusations of human rights violations.)

In the course of the administration of Mexico’s president, Andrés Manuel López Obrador, the navy has moved nicely past its most important enforcement and safety mission and into a wide range of profitable companies.

It constructed and operates Mexico Metropolis’s new airport and is setting up a lot of the nation’s largest tourism undertaking, a $20 billion, almost 1,000 mile railroad that it’s going to additionally handle as soon as accomplished. The armed forces are additionally now in command of the nation’s customs, one among Mexico’s greatest revenue turbines, with anticipated revenues of $59 billion for 2022.

Such duties, analysts warn, give the navy the flexibility to boost cash by itself and will undermine Mexico’s steadiness of energy.

On the similar time, in Nuevo Laredo, simply throughout the border from Texas, the navy’s lengthy observe file of abuses has bred deep resentment.

Mr. Ramos’ group has documented 18 instances of human rights violations linked to the navy since 2018, together with executions, rape and torture of civilians. However just one has gone to trial.

In a single case, a 4-year-old lady, Heydi Mariana, was shot and killed final August when the automobile she was using in got here underneath fireplace from troopers. A minimum of 16 bullets ripped by the car.

The navy mentioned the lady was killed throughout a confrontation with criminals, however has not offered proof. Nobody has been charged within the case.

“My daughter was going to kindergarten,’’ mentioned the lady’s mom, Cristina Rodríguez, 26, who added that troopers confirmed up at Heydi’s funeral, a transfer the household interpreted as an act of intimidation. “She was not a delinquent.’’

The evening earlier than the February assault on the pickup truck, the victims, all of their 20s, had been at an area nightclub to toast the information that Mr. Suárez was going to be a father.

After piling into Mr. Suárez’s truck, they handed 4 navy automobiles carrying 21 troopers that began pursuing the lads. In an announcement, the navy mentioned the troopers had heard gunshots from the route of the pickup.

The account of what occurred subsequent relies on interviews with the survivors, relations of these killed, their attorneys and the federal government’s report.

The troopers rammed one among their automobiles into the truck with out figuring out themselves or asking them to cease, the survivors say, an announcement confirmed by the Nationwide Fee for Human Rights.

The influence compelled the truck to crash exterior the house of Sara Luna, 60.

The troopers had been already firing, Ms. Luna says, including that she later counted 64 gunshots hanging her residence.

The gunfire lasted about quarter-hour, she says.

When it ended, she and her husband opened their entrance door a crack and noticed troopers standing over bleeding our bodies. The troopers ordered them inside.

Alejandro Pérez Benitez, 21, one of many two survivors, says he was within the pickup truck along with his brother when the taking pictures began.

One other occupant, who had been shot, stumbled out of the truck exterior Ms. Luna’s residence, asking troopers for an ambulance, Mr. Pérez says. They shot him once more and killed him, Mr. Pérez says.

Mr. Pérez acquired out of the truck, at which level a soldier compelled him onto his knees at gunpoint.

“‘Kill him, kill him so there isn’t any proof,’” he remembers one other soldier yelling.

The troopers made him lay facedown subsequent to his brother.

Then, Mr. Pérez says, they shot his brother within the again. As he lay in a pool of his brother’s blood, Mr. Pérez might hear an ambulance — however the troopers blocked it from arriving for over an hour.

Mr. Pérez says he put a hand on his brother’s physique. It began to go chilly. He kissed him.

Mr. Pérez says he was then compelled to tape a confession that he had shot on the troopers first.

Luis, 25, a barber who additionally survived, remembers rising from the automobile with bullet wounds to his lungs and abdomen. He says he was additionally thrown onto the pavement by the troopers and shot within the again.

The troopers accused him of making an attempt to run away.

“I informed them, ‘How am I going to run, I’m bleeding to demise,’” he says.

Paramedics had been ultimately in a position to take Luis to a hospital, the place he was put in a medically induced comma. His full title is being withheld as a result of he fears retaliation from the navy.

Humberto Suárez, the daddy of the American sufferer, wakened that morning anticipating to arrange a catfish he had caught to have fun his son beginning a household.

Quickly after, he obtained a name that his son was useless. He rushed to the scene to seek out his son’s bloodied stays splattered throughout the truck’s flooring.

Days later, Mr. Suárez says, a navy consultant met with him and relations of the opposite victims to debate a monetary settlement, a typical tactic by the navy, analysts say, to attempt to dissuade households from going to the media or to attempt to take instances to civilian courts.

“They didn’t come to say ‘we’re sorry,’” he says of the assembly, which he secretly recorded and shared with The New York Instances. “They got here to ask how a lot we needed, as if our sons had been canines.”

Emiliano Rodríguez Mega contributed reporting from Mexico Metropolis.