The grainy Border Patrol video of the Mexico border shows what looks like an adult atop a 14-foot barrier with a toddler, who is hoisted over the side and dangled by one arm before being dropped to the ground far below. The same then happens with a second child.

As the children slowly pick themselves up off the ground, two larger figures are seen running away on the other side of the border.

Border agents quickly responded to that remote section of the border near Mount Cristo Rey, N.M., on Tuesday evening and found two Ecuadoran toddlers, sisters ages 3 and 5, according to Customs and Border Protection officials. The girls were taken to a hospital for evaluation and were medically cleared. As of Wednesday afternoon, they were being held by the Border Patrol and waiting to be transferred to the care of the Department of Health and Human Services.

A screenshot from a video showing two toddlers getting dropped over a border barrier in the New Mexico desert on Tuesday.

The video is the latest reminder of the dangers facing the hundreds of children and teenagers who are arriving at the southwestern border each day, often without their parents. Earlier in March, a 9-year-old child from Mexico drowned while trying to cross the Rio Grande near Eagle Pass, Tex., and a 6-month-old baby was dropped into the river near Roma, Tex., but was rescued, according to local officials.

Homeland Security Secretary Alejandro Mayorkas blamed these incidents on smugglers.

“The inhumane way smugglers abuse children while profiting off parents’ desperation is criminal and morally reprehensible,” Mayorkas said in a statement. “There can be no doubt that children are exceptionally vulnerable when placed in the hands of smugglers. There is grave risk they will be exploited and harmed.”

Sickness, abuse, treacherous terrain, isolation, kidnapping and violence are a small sampling of the myriad dangers migrant children face when traveling — with or without their parents — thousands of miles north to the United States’ southwestern border. The odyssey of pain, hunger and doubt often doesn’t end at the river or desert crossing.

From the moment they leave their homelands, children are exposed to the perils of traveling by any means available or affordable. Migrants recently crossing the border in the Rio Grande Valley in Texas told The Washington Post they walked for hundreds of miles, boarded buses of all kinds, took rides from motorists and hopped on trains. Traveling in large groups, often called “caravans,” can offer the safety of numbers, but over the length of the journey, they often splinter into smaller groups.

In each of those scenarios, migrants of all ages — but especially children and teenagers traveling without their parents — have no way of knowing whether a driver, smuggler or fellow traveler will protect them or abandon them to violence or crime. The tales of robbery, kidnapping and sexual assault are all too common details in the accounts of migrants and reports from human rights groups documenting the horrors.

Helen Perry, executive director of Global Response Management, a nongovernmental organization that provides medical care to asylum seekers in Mexico, said her organization has treated children bearing the scars of beatings, genital mutilation and torture endured in the journey.

“They flee horrible situations to encounter horror on the road,” she said, recalling how one woman had the name of the gang that raped her carved into her abdomen with a knife. “I wish I could tell you I have only one or two of those stories. But it just never ends.”

Latin American criminal organizations usually control border crossings, charging hundreds of dollars to migrants seeking entry into the United States and punishing those who fail to pay, according to advocates for the migrants.

Reaching Mexican border states is no end to the trials. Families reported being kidnapped at bus stations in the border cities of Reynosa and Nuevo Laredo, Mexico. Migrants of all ages are easy targets for extortion and ransom, but children and teenagers, particularly those traveling without parents, are far more vulnerable, experts say.

The weather, wildlife and exposure of traveling in the Southwestern United States can quickly become life-threatening. The deserts of New Mexico and Arizona are littered with the remains of migrants who ran out of water, succumbed to a snake bite or were abandoned by smugglers along the route, according to advocates.

Children are not exempt from the callousness of their traffickers — a message CBP officials repeat consistently and one that members of the Biden administration have taken up in recent weeks as an unprecedented number of unaccompanied children have arrived at the border.

The Biden administration was on pace to take in more than 17,000 unaccompanied minors in March, far more than the previous record of 11,861 in May 2019. The administration has struggled to shelter and care for these children as they await placement with a vetted relative or parent already living in the United States or another sponsor.

Thousands of children have been held in CBP facilities for days longer than legally allowed because there are not enough beds available in shelters run by HHS. That has led to severe overcrowding during a pandemic.

A small group of journalists were allowed to tour one of these facilities in Donna, Tex., on Tuesday and observed children and teenagers packed into small rooms created from plastic sheeting. As of Tuesday, the facility held 3,400 unaccompanied minors and 700 members of migrant families.

Oscar Escamilla, acting executive officer for the Border Patrol’s Rio Grande Valley sector, told reporters that these “pods” have become so crowded that he worried the youngest children would be harmed, so he moved them to a less congested area. There, reporters saw a 17-year-old caring for an infant and an 11-year-old boy caring for his 3-year-old sister.

“I’m a Border Patrol agent,” Escamilla said. “I didn’t sign up for this.”