LOS ANGELES (KTLA) — A multi-agency investigation in Southern California led to the recovery of 33 children who had been missing, including eight who were sexually exploited, the FBI announced Friday.

Two of the children were rescued multiple times during Operation “Lost Angels.” They were apparently on the “track,” a term used to describe a known location for sex trafficking, officials explained.

The investigation began on Jan. 11, during Human Trafficking Awareness Month. More than two dozen agencies participated, including the Los Angeles police and sheriff’s departments, the National Center for Missing and Exploited Children, the California Department of Child and Family Services and nongovernmental victim advocacy organizations.

“Several other victims located had been sexually exploited in the past and were considered vulnerable missing children prior to their recovery,” the FBI said in a news release.

One suspected human trafficker was arrested on state charges. In addition, some of the minors were arrested on suspicion of probation violations, robbery and other misdemeanors, and one child was the victim of a noncustodial parental kidnapping, officials said.

Authorities did not elaborate on where the victims were located, nor did they provide any additional information on the suspect.

Officials say the caseload for sex and labor trafficking-related crimes has “increased significantly” in the last several years.

Last year, the FBI initiated 665 human trafficking investigations across the country, resulting in the arrests of 473 people, officials said. And as of November, there were more than 1,800 pending trafficking investigations, including those involving minors exploited through commercial sex trafficking. 

The FBI leads 86 child exploitation and human trafficking task forces in the U.S., and participates in anti-trafficking coordination teams in 12 offices, including in Los Angeles.

“Human trafficking is a pervasive and insidious crime that threatens the safety of our young people, who are the future of our communities,” LAPD Chief Michel Moore said in a statement. “We can only begin to take back the future of our youth with the strong partnerships forged between outstanding service providers and law enforcement.” 

The FBI will work to ensure the victims are provided with any resources they may need, including medical requirements, legal services, housing, employment, education, job training and child care, officials said.

The extensive joint operation involved the following law enforcement agencies: