When smoke began billowing out of a migrant detention center in the Mexican border city of Ciudad Juarez, Venezuelan migrant Viangly Infante Padrón was terrified because she knew her husband was still inside.

The father of her three children had been picked up by immigration agents earlier in the day, part of a recent crackdown that netted 67 other migrants, many of whom were asking for handouts or washing car windows at stoplights in this city across the Rio Grande from El Paso, Texas.

In moments of shock and horror, Infante Padrón recounted how she saw immigration agents rush out of the building after fire started late Monday. Later came the migrants’ bodies carried out on stretchers, wrapped in foil blankets. The toll: 38 dead in all and 28 seriously injured, victims of a blaze apparently set in protest by the detainees themselves.

“I was desperate because I saw a dead body, a body, a body, and I didn’t see him anywhere,” Infante Padrón said of her husband, Eduard Caraballo López, who in the end survived with only light injuries, perhaps because he was scheduled for release and was near a door.

But what she saw in those first minutes has become the center of a question much of Mexico is asking itself: Why didn’t authorities attempt to release the men — almost all from Guatemala, Honduras, Venezuela and El Salvador — before smoke filled the room and killed so many?

“There was smoke everywhere. The ones they let out were the women, and those (employees) with immigration,” Infante Padrón said. “The men, they never took them out until the firefighters arrived.”

“They alone had the key,” Infante Padrón said. “The responsibility was theirs to open the bar doors and save those lives, regardless of whether there were detainees, regardless of whether they would run away, regardless of everything that happened. They had to save those lives.”

Immigration authorities said they released 15 women when the fire broke out, but have not explained why no men were let out.

Pope Francis on Wednesday offered prayers at the end of his general audience for the victims who died in the “tragic fire.”

Surveillance video leaked Tuesday shows migrants, reportedly fearing they were about to be moved, placing foam mattresses against the bars of their detention cell and setting them on fire.

In the video, later confirmed by the government, two people dressed as guards rush into the camera frame, and at least one migrant appears by the metal gate on the other side. But the guards don’t appear to make any effort to open the cell doors and instead hurry away as billowing clouds of smoke fill the structure within seconds.

“What humanity do we have in our lives? What humanity have we built? Death, death, death,” thundered Bishop Mons. José Guadalupe Torres Campos at a Mass in memory of the migrants.

Mexico’s National Immigration Institute, which ran the facility, said it was cooperating in the investigation. Guatemala has already said that many of the victims were its citizens, but full identification of the dead and injured remains incomplete.

U.S. authorities have offered to help treat some of the 28 victims in critical or serious condition, most apparently from smoke inhalation.

For many, the tragedy was the foreseeable result of a long series of decisions made by leaders in places like Venezuela and Central America, and by immigration policymakers in Mexico and the United States, as well of residents in Ciudad Juarez complaining about the number of migrants asking for handouts on street corners.

“You could see it coming,” more than 30 migrant shelters and other advocacy organizations said in statement Tuesday. “Mexico’s immigration policy kills.”

Those same advocacy organizations published an open letter March 9 that complained of a criminalization of migrants and asylum-seekers in Ciudad Juarez. It accused authorities of abusing migrants and using excessive force in rounding them up, including complaints that municipal police questioned people in the street about their immigration status without cause.

President Andrés Manuel López Obrador offered sympathy Tuesday, but held out little hope of change.

He said the fire was started by migrants in protest after learning they would be deported or moved.

“They never imagined that this would cause this terrible misfortune,” López Obrador said.

Immigration activist Irineo Mujica said the migrants feared being sent back, not necessarily to their home countries, but to southern Mexico, where they would have to cross the country all over again.

“When people reach the north, it’s like a ping-pong game — they send them back down south,” Mujica said.

“We had said that with the number of people they were sending, the sheer number of people was creating a ticking time bomb,” Mujica said. “Today that time bomb exploded.”

The migrants were stuck in Ciudad Jaurez because U.S. immigration policies don’t allow them to cross the border to file asylum claims. But they were rounded up because Ciudad Juarez residents were tired of migrants blocking border crossings or asking for money.

The high level of frustration in Ciudad Juarez was evident earlier this month when hundreds of mostly Venezuelan migrants tried to force their way across one of the international bridges to El Paso, acting on false rumors that the United States would allow them to enter the country. U.S. authorities blocked their attempts.

After that, Ciudad Juarez Mayor Cruz Pérez Cuellar started campaigning to inform migrants there was room in shelters and no need to beg in the streets. He urged residents not to give money to them, and said authorities removed migrants intersections where it was dangerous to beg and residents saw the activity as a nuisance.

For the migrants, the fire is another tragedy on a long trail of tears.

About 100 migrants gathered Tuesday outside the immigration facility’s doors to demand information about relatives. In many cases, they asked the same question Mexico is asking itself.

Katiuska Márquez, a 23-year-old Venezuelan woman with her two children, ages 2 and 4, was seeking her half-brother, Orlando Maldonado, who had been traveling with her.

“We want to know if he is alive or if he’s dead,” she said. She wondered how all the guards who were inside made it out alive and only the migrants died. “How could they not get them out?”