SACRAMENTO COUNTY (CBS13) — Truck drivers are helping crack down on human trafficking.

On Tuesday, the California Trucking Association announced it’s partnering with Sacramento-area law enforcement to combat human trafficking. They’re the eyes and ears of the nation’s highways and roads.

More than half a million truck drivers in California so far have been trained to spot the warning signs.

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“You need to pay attention out here,” said truck driver Kevin Kimmel.

Kimmel’s bravery saved a young girl who was being trafficked in 2015. He was on an assignment in Virginia when saw a blacked out RV parked at a truck stop. Kimmel says he saw what appeared to be a sexual transaction, and what he saw next led him to call the police.

“I saw what I thought was a girl looking out the window, she was abruptly pulled back and the black shade was pulled,” Kimmel said.

Kimmel’s story is driving the California Trucking Association to crack down on human trafficking.

“They are trained to be vigilant, and they see things that other people don’t see,” said Kylla Lannier, deputy director of the CTA.

The association has trained more than half a million truckers across the state to watch out for young women who appear out of place, and who may be with someone who appears suspicious.

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Those efforts haven’t gone unnoticed.

“They have made close to 2,000 calls to the National Human Trafficking hotline, generating over 500 cases of sex trafficking, involving over a thousand victims,” Lannier added.

Truckers Against Trafficking is another prominent program across the country. Al Hoelscher is a member and has a sticker on the side of his window to let victims know he’s watching when no one else is.

“If they give us a sign of some sort, somebody is getting called, you will have law on you quickly,” Hoelscher said.

Victim advocate agency, WEAVE INC., says it helped almost 300 trafficking victims in the past year, thanks to citizens with a heightened awareness.

If you or someone you know needs assistance, please contact the National Human Trafficking Resource Center at (888) 373-7888.