A 3-month-old baby and a 5-year-old child were rescued in October in Denver as part of a global effort that also saved 82 other minors from underage human trafficking rings across the US and dozens more in other countries.

The sisters were rescued in Denver by an undercover agent who'd been offered for $600. The alleged trafficker, a friend of the children’s family, was placed under arrest.

The trafficker is one of 120 others who were arrested earlier this month as part of Operation Cross Country XI, a three-day, nationwide effort that focused on underage human trafficking.

Take Action: Tell World Leaders to Redouble Their Efforts By Amending Laws to Prevent Sexual Violence

A total of 84 minors — who averaged around 15-years-old — were rescued in the US, the FBI announced.

“Unfortunately, the number of traffickers arrested — and the number of children recovered — reinforces why we need to continue to do this important work,” FBI Director Christopher Wray said. “This operation isn’t just about taking traffickers off the street. It’s about making sure we offer help and a way out to these young victims who find themselves caught in a vicious cycle of abuse.”

The operation was the largest ever in the history of the initiative, which began in 2003 as part of the FBI’s Innocence Lost National Initiative.

Read More: One-Third of Trafficked Humans Are Kids, UN Says

Over 400 law enforcement organizations were involved in the operation which took place in hotels, truck stops, casinos, street corners and online, the FBI said.

For the first time, several countries around the world were also involved.

Law enforcement partners from Cambodia, the Philippines and Thailand each had their own respective operations, recovering 25 children, including a 2-year-old girl. In Canada, authorities recovered 16 children.

For these young survivors, life may never be the same.

Officials are working with a protective services agency to house the two girls. For other young survivors, resources and assistance will be offered through the FBI’s Office for Victim Assistance.

“Depending on the level of need, victims are offered medical and mental health counseling, as well as a number of other services,” the FBI said.

The primary role of the #FBI's national multi-agency initiative—to recover children who are being trafficked. https://t.co/cMd7FgDBMF

— FBI (@FBI) October 18, 2017

Human sex trafficking has become a trade so lucrative that it knows no borders.

Every year, an estimated 800,000 women and children are trafficked across international borders, according to Soroptimist, a global volunteer organization working to improve the lives of women and girls. That figure doesn’t even include the number of women and girls trafficked within countries.

“It can happen to anybody,” a sex-trafficking survivor identified as Ali shared in a video distributed by the FBI after the massive operation.

Read More: Human Trafficking Survivor, Raped 43,200 Times, Has Dedicated Her Life To Helping Sex Slaves

A Philadelphia native, Ali has a master’s degree and described how her heroin addiction made her vulnerable to traffickers.

“In the beginning, it’s easy for them to manipulate you when you have nothing and they’re literally providing you with everything,” she shared. “I was willing to sacrifice — enduring that because without that person, I thought I had nothing.”

Children, officials say, are especially vulnerable.

Bradley Myles, CEO of the Polaris Project, which launched a human trafficking hotline, said that traffickers often prey on those with trauma in their history, including abuse, assault, or rape.

The National Center for Missing and Exploited Children (NCMEC) estimates that one out of six runaways reported in the US are thought to be victims of sex trafficking. Studies have shown that 50 to 90% of those victims have been involved in the child welfare system.

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The same study found that internationally, 76% of refugee and migrant children have been victims.

“We are seeing about an average of 23 cases a day [in the US alone],” Myles told CNN. “So we need that daily drumbeat of a 24-hour response throughout the country.”

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