Border Patrol agents swarmed into a hot dusty orange orchard near McAllen, Texas, on the hunt for a group of illegal immigrants spotted crossing the Rio Grande River from Mexico.

With a helicopter directing from above, the agents claimed positions around the acres of trees with trucks and SUVs. Others rode ATVs and dirt bikes up and down the orchard’s rutted paths while a K-9 team worked frantically back and forth, tracking multiple scents.

Eventually, 14 young men were pulled from hiding places under the trees, handcuffed and lined up on the ground, waiting for a transport van.

Answering questions in Spanish, more than half the detainees admitted being busted before. One said he’d been caught trying to illegally enter the U.S. more than ten times.

A few miles away, another group of agents found 16 migrants from Honduras, including women, children and unaccompanied minors. These people weren’t running from the uniformed officers, they sought them out to apply for asylum, hopeful they’d be processed and allowed to stay in America.

This is typical in the Rio Grande Valley sector, where Customs and Border Protection made more than 21,000 arrests in October alone, nearly 900 in a single day. A spokesman says about half are humanitarian cases. The other half are considered criminals who will sometimes try to use the migrants as a smokescreen, joining groups of 30 to 50 crossing at once, trying to blend in or peel away when possible.

CBP has remote cameras and sensors that alert to movements near the border, but its resources are stretched thin. About 3,100 agents cover this rough and rocky stretch of 277 miles, a small chunk of the nearly 2,000 miles dividing the U.S. from Mexico.

The agents know they can’t catch all the illegal crossers, calling the rest “got aways.” They understand why so many seek a better life in America. They also know there are often gang members, sex offenders, killers and other criminals trying to sneak in, so they welcome the help from the 5,200 U.S. military active duty soldiers deployed to the region, offering logistical support, building temporary fencing and providing extra eyes in the sky and along the horizon.

On background, some of the border agents suggest a zero-tolerance policy and a better wall would go a long way toward reducing the illegal traffic.

After the hour-long cat-and-mouse game in the orchard ends with the 14 in custody, I ask one agent if this was a typical day on the job.

He looked at me, shook his head and smiled.

“Slow day, bro,” he said.