But it shows another side of a new reality taking shape south of the US-Mexico border.
As a mother and daughter heading for the Rio Grande, he is followed by a man in military clothes.
He reaches for the woman's backpack and pulls her away from the river, which she can no longer reach. Another man, wearing a camouflage and holding a big gun in his hand, blocks their way.
Nightly news broadcasts discussed it. Reporters offended Mexico's president during his daily press conference.
The photo shows several Nicaraguan migrants caught by troops on Friday as they tried to cross the border, Martínez told CNN. A woman had traveled with her husband and two daughters. They made it across the river. She did not do it.
The reactions to the photo are inconsistent.
Martínez, a journalist in Juárez for more than a decade, said the changing dynamics in the border town were felt with the recent troop surge in the city.
"It's very different from what we're used to," she said. "And very visible."
The reactions to the photo – and what it represents – were mixed.
"There are as many comments as against it," said Martínez.
Many critics agreed with a common response: Mexico becomes Trump's boundary wall.
A cartoonist drew his own version of the photo and replaced the faces of the troops with those of Mexican President Andrés Manuel López Obrador and Mexican Foreign Minister Marcelo Ebrard. In the background, the US President looks over a border wall.
"National Guard … by Trump", it says in the headline of the cartoon.
Mexican columnist Denise Dresser shared the photo and others in the series with a pungent description: "Here the National Guard shows that it is a bourgeois character." his "respect for human rights", his "training" in the exercise of police work and his clear conversion to the border police, now in the service of Donald Trump. "
Reporter López Obrador took part in Tuesday morning's Mexican President's press conference Questions about what was in the photo were harassing.
A journalist asked, "Because you could even see them separating a family. It is very bad. I wanted to ask you to respond to those who say that Mexico is building a wall on the border with these 15,000 National Guard troops. "19659002]" It's not like that, "López Obrador replied." It's more than anything, what governs the entry to the south. When these cases occurred, they were not instructed to do so. It's work that matches immigration officials, not the military. But it could have happened. "
Mexico is getting harder in immigration
This month, a CNN team observed migrants seeking help in a detention center in southern Mexico.