It seemed like such a normal activity – a 16-year old girl riding her bike to a friend’s house one afternoon. But by that evening, the girl had not called her parents as promised. And her phone was shut off.

Maureen and David knew that their daughter and the friend she had visited were missing – and life became anything but normal. After the parents spent hours calling friends, family and neighbors, meeting with police and even hiring a private investigator, they were no closer to finding their daughter than they were on the Friday

afternoon she left.

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“We knew the police were treating her like a runaway and they just weren’t doing much,” Maureen, whose daughter’s first name is being withheld for safety reasons, tells PEOPLE. “We were trying to do all we could ourselves, but it was like looking for a needle in a haystack. You could go broke hiring people to help you and still not find anything.”

Image zoom Courtesy: Jena Willard and Jose Navas Courtesy of Saved In America (SIAM)

That’s because the girls were victims of a gang that sold them into sex trafficking. Their case was among the 7,621 reported cases of human trafficking reported to the National Human Trafficking Hotline in 2016. California, the girls’ home state, leads the list in the number of human trafficking cases in the United States. Texas, Florida, Ohio and New York follow.

About three weeks after the girls’ Jan. 29 disappearance in 2016, the family contacted Saved In America (SIAM), based in San Diego. The group’s co-founder is renowned private investigator Joseph Travers, a chaplain whose extraordinary work into police harassment was profiled in a 1989 issue of PEOPLE. When he founded SIAM, Travers recruited retired U.S. Navy Seals, police detectives and other specialists into the all-volunteer group.

“I knew that street gangs, prison gangs and cartels took over drug trafficking in the 1980s and then they took over sex trafficking at the turn of the century,” said Travers. “When I read about [the 2009 disappearance of] Brittanee Drexel, who disappeared off the face of the planet, I just knew gangs were involved.”

The abduction, rape and horrific death of the Rochester, New York, teen inspired Travers to develop an organization that would rescue young women and men from human trafficking rings.

One such case was the daughter of David and Maureen, who, along with her friend, took a ride from an older man driving a BMW who took them to Los Angeles.

From there they were sold into sex slavery.

Less than a week after Travers’ team joined the case, the daughter of David and Maureen was rescued in Compton, California.

Travers is quick to point out that funding from supporters makes such rescues possible. Travers secured funding for the venture from several sources including the William D. Lynch Foundation — and recruited, trained and licensed his all-volunteer team.

SIAM investigates the cases of missing juveniles through a host of channels, conducts surveillance and then works with local police and the victims’ parents to rescue the child.

The group has also established a system to transfer the victims right into treatment.

Most of those who know SIAM are impressed by the high-tech investigations and dramatic rescues, but Special Operations Chief Toshiro Carrington said Travers’ planning and organization are responsible for the group’s success.

“What I do is easy,” says Carrington, a former U.S. Navy Seal. “Our goal is to work within the system as it exists.”

Travers has a host of letters from law enforcement officials praising the team, its practices and successes – 58 out of 58 rescued to date.

“It is partnerships such as this that play a significant role in law enforcement today, not only from a public safety standpoint but also as an opportunity to make a difference in the lives of those who have been victimized,” wrote Mike Williams, Sheriff, Duval County Florida in a 2016 letter to Travers.