Counterfeit NFL jerseys continue to be a big problem for the NFL and licensed apparel vendors, but fans are willing to take a risk on fake jerseys because of the cost savings. (7:01)

The NFL, in cooperation with government authorities, announced on Thursday that it had seized a record $13.6 million worth of counterfeit NFL merchandise this season in a nationwide enforcement effort called "Operation Red Zone."

That total included a bust in Warwick, R.I., in September, when the U.S. Immigration and Customs Enforcement's (ICE) Homeland Security Investigations, with an assist from U.S. Customs and Border Protection and U.S. Postal Inspection Service, seized 226 boxes containing 4,016 counterfeit jerseys. It also includes 160,000 Super Bowl-related pieces of memorabilia discovered in recent days.

"Organized criminals are preying on that excitement, ripping consumers off with counterfeit merchandise and stealing from the American businesses who have worked hard to build a trusted brand," said ICE director John Morton, in a statement. "The sale of counterfeit jerseys and other sports items undermines the legitimate economy, takes jobs away from Americans, and fuels crime overseas. No good comes of counterfeiting American products -- whether NFL jerseys, airbags, or pharmaceuticals -- and we must go after the criminals behind it."

All this is just the tip of the iceberg, as an "Outside The Lines" investigation that will air Sunday has discovered. In the past couple of years, stopping counterfeiting has gotten more challenging as more websites, mostly coming out of China, have gone directly to the consumer. It is only a crime to sell counterfeit gear, not to buy it.

Counterfeiters have also done more business as the price of jerseys has risen. A knockoff of a stitched official Nike jersey that retails for $135 sells on these sites for as little as $20 and often includes free air shipping from Asia that allows a consumer to have the package in eight to 10 days. Nike is in the first year of supplying jerseys to the NFL. Counterfeiters also offer variations of products that licensees don't, such as camouflage jerseys with team logos on them.

"If you were to say who is our largest competitor, I would say counterfeit," Jamie Davis, president of Fanatics, one of the largest online sports retailers, told "Outside the Lines." The company, which runs many official online stores, including the NFL site, projects it will do $1 billion in business this year.

Davis says that, while counterfeiters often use the same pictures to mislead consumers, what fans get when it arrives on their doorstep is a different story, ranging from misspellings to loose stitches to colors that fade with a single wash. Davis showed ESPN a Victor Cruz jersey that was ordered from China that had a Super Bowl XLV patch on it. Cruz and the New York Giants played in Super Bowl XLVI. When these mistakes occur, Davis says there's often no recourse, as many counterfeit businesses don't have any customer service.

Catching counterfeiters has proved to be a near-impossible task. Although the NFL told ESPN it shut down an astounding 4,200 websites this season, it didn't completely shut down all those businesses.

"It's a big game of Whack-A-Mole, where we try to go after counterfeiters and they pop up somewhere else," said Anastasia Danias, the NFL's vice president of legal affairs.

Eric Feinberg, founder of the consumer advocacy group FAKE ("Fans Against Kounterfeit Enterprise"), says that, after sites are disabled, they pop up in as soon as 48 hours, adding a word -- or even just a couple of letters -- to the old website address. The businesses are even harder to track down, Feinberg said, because domain names are often registered to fake addresses, and domain registry sites -- lured by the business of selling another name -- continue to sell what the counterfeiters want.

"It's out of control," Feinberg said.

While one could make the argument that fewer consumers are being tricked -- and instead are knowingly taking their chances with counterfeit websites -- Feinberg says he is concerned with sites like eBay, Amazon and Facebook, which take limited responsibility for counterfeit merchandise being sold on or through their sites.

Both Amazon and eBay have won court decisions in recent years that don't obligate them legally to shut down counterfeit auctions. Feinberg showed "Outside the Lines" counterfeit ads that not only appear frequently on Facebook pages of those who identified themselves as NFL fans, but also come directly through the email tied to the Facebook account.

Much of the communication through the league and authorized dealers has been regarding how not to be duped by counterfeiters, but the challenge is that many fans today know exactly what they are doing when they go to these sites.

Preston Burns is one of those fans. He and his friends have ordered many jerseys from a counterfeit website. His latest purchase, a stitched Colin Kaepernick jersey and an Aldon Smith camouflage jersey, cost him $70, including free shipping.

"Pretty much everyone at the stadium would think this is an authentic jersey purchased for over $200 from some official NFL outlet," Burns said of the Kaepernick jersey.

The biggest difference? You can't even buy an official stitched version of a Kaepernick jersey. Due to his late emergence on the scene, Nike only has the lowest-tier jersey for Kaepernick, the screen-on name and number jersey, available to the public for $100.

"I think this one puts me closer to the gameday experience," Burns said. "Closer to what the players are wearing on the field."

Nike spokesman Kejuan Wilkins said the company does what it can to protect itself and retailers against counterfeiters, but also wants to protect the fan.

"We believe that we make the best product for every stage of the game," Wilkins said, in a statement provided to "Outside the Lines." "NFL fans deserve the same level of design and execution as the pros."

Danias, the NFL's counsel, says the league hears from plenty of fans each year who receive inferior products from counterfeiting sites. But the scary part is the number of people who are ordering fake jerseys that the league isn't hearing from.

Guys like Burns and his friends order counterfeit jerseys that are pretty close to the real thing and show up with tags with holograms on them.

At his tailgate before this year's playoff game against the Green Bay Packers, Burns was pointing out all the people wearing jerseys that he thinks were purchased from sites selling them illegally.

Said Burns: "I think a lot of people at 49ers games today are wearing jerseys from China, probably more people than are wearing the real thing."