AUSTIN, Texas - It's a crime that's easy to miss, unless you know what to look for.

"It is a hidden crime, and I believe it's happening in all communities," said Refugee Services of Texas’ Survivors of Trafficking Empowerment Program Supervisor Rachel Alvarez.

The Polaris Project recently found Texas has the second-highest number of human trafficking incident in the United States.

"Texas is definitely becoming an epicenter nationally for human trafficking," said President and CEO of Allies Against Slavery John Nehme.

Alvarez said the crime doesn't discriminate: "I've seen trafficking cases and helped victims from all different communities - from at-risk populations to vulnerable communities to affluent communities, as well."

Human traffickers tend to make the most of major highways.

"There is a huge element of transporting victims from one place to another,” Alvarez said. “There's a lot of transporting by the trafficker, the controller, to disorient the victim."

Several trafficking hot spots fall along the I-35 corridor. Nehme said many cases have been reported in Dallas, Austin, San Antonio and Houston.

"People also looking for opportunities in cities often falling prey to traffickers who dangle the carrot of false promises in front of them and ultimately exploit them," he said.

While trafficking is more common in urban areas, advocates said it also depends on the type of trafficking.

"Some of our labor cases have been, obviously, related to agriculture in the (Rio Grande) Valley or the Panhandle," said Nehme.

While there have been 313,000 trafficking victims identified by University of Texas researchers, experts put the actual number higher. But, advocates say, while that information is disturbing, it's also a sign of progress.

"We're starting to get the better tools, better research, better insight to how to move forward proactively and tactically to take this down," Nehme said.

A strategy that could impact what may be the most elusive crime in the Lone Star State. Last year, the Polaris Project reported that human trafficking increased 35 percent nationwide.

California has the most reported trafficking incidents, followed by Texas.