NEAR FALFURRIAS – From tough terrain to scorching heat, people who cross the U.S.-Mexico border illegally face challenges every day.

Border Patrol agents say smugglers often don’t prepare crossers for the dangerous trek. Getting through the fence is only half of their journey and in the extreme heat, it can be deadly.

“The guys are walking anywhere from 20 to 50 miles through desert terrains, with only the amount of water and recourses they can carry on their back,” says Agent Daniel Reyes with Border Patrol Search, Trauma and Rescue Unit.

They say once they get a call about a group in the field, it’s their job to intercept that group before anyone succumbs to the elements.

First Warn 5 Meteorologist Cecilia Gutierrez went with border patrol agents to give us a firsthand look of what they go through.

Watch the video above for the full story.