MEXICO CITY — Mexico’s new president acknowledged Tuesday that three civilians including a child died in two shootouts involving the military last week in a violent border city.

President Claudia Sheinbaum said a soldier was killed in one of the shootouts, as well as two adults and an 8-year-old girl. She said the events on Friday and Saturday are under investigation.

But Sheinbaum gave no sign of backing away from the outsized role that she and her predecessor have given to the armed forces.

The events in Nuevo Laredo, across the border from Laredo, Texas, started Friday when a nurse, her husband and son found themselves on a road where soldiers were pursuing suspects’ vehicles. The husband, Víctor Carrillo Martínez, told local media there was a confrontation and his wife died in the crossfire.

Sheinbaum said the soldier was apparently killed in an exchange of gunfire.

“It had to do with criminals who opened fire on an army vehicle,” she said. “It is very important to say that Nuevo Laredo is where criminal groups have carried out the most attacks on the army and the National Guard.”

The city has long been in the grip of the Northeast Cartel, an offshoot of the old Zetas gang.

The second incident in Nuevo Laredo happened Saturday, when the 8-year-old and her grandmother were driving to a store and were caught in the middle of a pursuit by soldiers or National Guard officers.

The grandmother told reporters that a military vehicle was pursuing an SUV and her car got stuck between them and the military opened fire.

The Human Rights Commission of Nuevo Laredo said a young man’s tortured body was found nearby in a truck that the army and National Guard had been pursuing.

Sheinbaum confirmed the two deaths, saying the shootings had involved the militarized National Guard.

“In case there has been any misbehavior by any member of the guard or the army, or any official, it will be punished,” she said.

The Defense Department, which controls the National Guard, said it had no immediate comment on the shootings.

Last week, the army was involved in another shooting that killed six migrants and wounded 10. In the incident near Tapachula, close to the border with Guatemala. soldiers claimed they heard “detonations” and opened fire on a truck carrying migrants from Egypt, Nepal, Cuba, India, Pakistan and El Salvador.

The dead included an 11-year-old Egyptian girl. The area is often used by migrant smugglers, but warring drug cartels also operate in the region.

Former president Andrés Manuel López Obrador, who left office Sept. 30, gave the military an unprecedentedly wide role in public life and law enforcement. He created the militarized Guard and used the combined forces as the country’s main law enforcement agencies, supplanting police.

But critics say the military is not trained to do civilian law enforcement work.

“For decades, when the army and the marines have been used in law enforcement, complaints of human rights violations have skyrocketed,” said security analyst David Saucedo. “The armed forces operate with an extermination logic ... that is one of the reasons that many of us oppose militarization.”

Military analyst Juan Ibarrola denied there was a lack of discipline on the part of the army.

“This is not a lack of training. Remember, Mexican soldiers have been in the streets and on the highways for 30 years,” Ibarrola said. “A soldier knows very well he will not escape justice, unlike some others in Mexico.”

But both said it reflected the severity of attacks that soldiers deal with in some parts of Mexico.

“There is also a problem of increased criminal activity,” said Saucedo. “The National Guard, the army and the marines have been outgunned.”

“That is why these soldiers are on the defensive, on alert, and they open fire against the slightest indication of an attack against them.”

The head of the Nuevo Laredo rights committee, Raymundo Ramos, said the armed forces have been allowed to operate above any civilian authority.

“It appears nobody wants to touch the military in this country,” he said.