Editor's note: This story includes details some readers may find disturbing.
At a shelter for Venezuelan migrants in the Colombian border town of Villa del Rosario, Alondra Castillo pulls back her blouse to reveal black-and-blue welts on her arms and shoulders.
Castillo, 23, explains that she and about 80 other Venezuelans were crossing into Colombia last month on a clandestine trail controlled by drug smugglers. But it was night, and she and her 2-year-old son became separated from the group.
While she and her child stumbled around in the dark, five men surrounded them. Then, Castillo says, they raped her.
"They tied me up with my own clothes," she says, calmly recounting the harrowing details of the attack.
Human rights activists have reported a sharp increase in sexual assaults and human trafficking involving Venezuelan women and girls trying to reach Colombia ever since the border officially closed because of the coronavirus last March.
About 2 million Venezuelans have fled to Colombia since 2014, to escape food shortages, unemployment, hyperinflation and authoritarian rule. They used to enter Colombia at official crossing points with immigration offices and tight security. But with all frontier posts shut down, they must now cross on lawless smuggling trails where gangsters extort migrants, rob them and sometimes rape them.
Vanessa Apitz, a Venezuelan lawyer who runs an aid station on the Colombian side of the border that provides migrants with food and legal advice, says before the pandemic, she received reports of one or two rapes per week. Now, the numbers are soaring. Twenty-eight migrant women and girls were raped in a single week last year, she says.
"That's when we sounded the alarm and realized that something bad was happening," Apitz says.
Since the pandemic began, the rape of migrants has increased by 60%, she estimates. She and other experts say the true number of sexual assaults along the border is difficult to determine because Venezuelan migrants almost never report the crimes to Colombian police. Some victims believe they will be deported; others fear that revenge-seeking gang members will come after them.
All Apitz can do under these circumstances is lend a sympathetic ear and try to convince victims to seek medical care.
Questioned by NPR about sexual assaults along the border, José Palomino, chief of police of Cúcuta, Colombia's largest border city, says: "We have received information about the problem but not criminal complaints."
For decades, smugglers have used the network of clandestine cross-border trails to move everything from contraband liquor and gasoline to weapons and cocaine. But since the border closed 10 months ago, the dirt footpaths have become an obligatory route for migrants — and at times, a terrifying gauntlet. They must navigate several miles of no-man's land where Venezuelan and Colombian gangs often prey on female migrants. The assaults occur on both sides of the border.
Sobbing as she tells her story, a 34-year-old Venezuelan woman at the shelter in Villa del Rosario recounts how she tried to take precautions before crossing the border in November. She had been traveling on her own but joined a group of other migrants at the border, thinking there would be safety in numbers.
The woman wanted to cross during the day, but the group decided to slip into Colombia at night to avoid detection by Colombian police. Once on the Colombian side, the group dispersed in a wilderness region, leaving the woman on her own.
Suddenly, she says, three men hauled her into the bushes and raped her. Then they stole her luggage.
"What little I had they took," says the woman, who did not want to be named for fear of retaliation by those who raped her. "Given all the things that have happened to me, I should have died of a heart attack."
Ana Teresa Castillo, a Colombian who runs the shelter (and is no relation to Alondra Castillo), says she is tending to many more rape victims now than before the pandemic began. She blames the closing of official border posts as well as the fact that gangs often block the smuggling trails during daylight hours, forcing migrants to cross at night, when they are far more vulnerable.
"All this has led to more violence," Castillo says. "But the police don't do anything."
Sometimes the gangs lure female migrants across the border with false promises of jobs in Colombia, says María Cecilia Ibáñez, a lawyer in Bogotá for the rights group Women's Link Worldwide.
"Migrant women and girls are in very vulnerable conditions and they will take anything that they are offered," she says. "And then when they get to Colombia, they find out that they are actually there as victims of human trafficking and they are informed that they are there to engage in prostitution."
Some end up working as prostitutes in the Colombian city of Pamplona, a two-hour drive from the border. David Bernal, the city's top human rights official, says Pamplona is full of prostitution rings that force Venezuelan women and girls into the sex trade.
On a recent afternoon, Bernal met with a handful of Venezuelan prostitutes to discuss the murder of one of their coworkers. A few days earlier, the naked and strangled body of 28-year-old María Pernia had been found in her apartment.
It was unclear whether Pernia, who arrived in the city three years ago from the Venezuelan city of Barinas, had been coerced into the sex trade. But her roommate, a Venezuelan prostitute who did not want to give her name for fear of retaliation from the killer or killers, said Pernia had no other way to feed her 2-year-old son.
Despite Bernal's urging, none of the women were willing to speak to Pamplona authorities about Pernia's death because they feared retaliation from whomever was behind the killing.
Silence also reigns at the shelter in Villa del Rosario, where neither of the two women most recently alleging rape have filed a criminal report. They have even refused to go to the hospital to treat their wounds. But Alondra Castillo knows she will have to get a checkup sooner or later.
"I'm not using birth control," she says, "and just imagine if I'm pregnant."