With the number of undocumented immigrants on the rise, drug seizures at the border are drastically low. While it may seem the two issues are unrelated, some border experts are starting to believe there's more than just coincidence to the timing.

Their take? The influx of immigrants is causing Border Patrol agents to be overworked, and the exhaustion -- or simple distraction -- is making them more likely to overlook smugglers while dealing with immigration issues.

Smugglers are exploiting gaps within the border system coverage, experts say. And they're using groups of immigrants to do it. 

Sylvia Longmire, a retired Air Force captain and federal agent who wrote the book "Border Insecurity," told Fox News Latino that Border Patrol agents are extremely overworked now, having to work multiple shifts. 

The cartels are banking on sheer human exhaustion in order to pass drugs through undetected, and apparently, the route is working.

Chris Cabrera, the U.S. Border Patrol union representative in the Rio Grande Valley region, told the Washington Post that cartels will coordinate sending large groups of undocumented immigrants across the border, banking on them getting caught. While agents are busy with immigration issues, they send through the drugs. 

The area of the Mexican border that runs along south Texas has seen the largest issue with immigration has been in recent months. It is also an area controlled by a number of narco-traffickers -- with Los Zetas the most prominent -- and the groups appear to have built an intricate network of human trafficking and drug smuggling around the immigration issue. 

According to The Daily Beast, narco-traffickers have built upon "what was once a relatively informal and somewhat familial underground operation," and turned it into a "highly sophisticated human trafficking network." 

Coyotes, or paid-for-hire guides used by undocumented immigrants to navigate rough terrain, are the most commonly used method of getting across border lines. But it appears that what was once an unsophisticated method of crossing across the Rio Grande is now a convoluted amalgam of drug smugglers, coyotes, and cartels.

Texas Department of Public Safety Director Steve McCraw spoke at a news conference recently, stating that drug smugglers are jumping at chances to expand smuggling efforts, and noting that the situation could get worse.

"Certainly they are exploiting this opportunity," McCraw said.

With the number of undocumented immigrants crossing the border in the tens of thousands already, it is a prime time for cartels to take advantage of the issue. A record number of undocumented immigrants is expected by the end of the year, and the number could reach well above projections.

One of the biggest issues in recent months has been the overwhelming number of unaccompanied minors making their way into the United States.

Holding centers in the Rio Grande Valley are overcrowded and well-over capacity, and efforts to disperse the crowds have been met with opposition from residents in other states.

The most recent show of opposition took place in Murietta, California, where anti-immigration protesters blocked roads, causing buses full of immigrant children bound for California facilities to reroute to San Diego. 

President Obama urged the nation to push for immigration reform during his Independence Day ceremony, where he was swearing in 25 new United States citizens who earned citizenship by way of military service.

The President has been vocal in recent days about his move to change immigration laws in response to the crisis, with or without the support of Congress.