9Wants to Know has learned some of the websites were registered through Denver-based domain services, including uggbootsclearanceoutletstores.com and bootsforwomenonsaleonline.com.

Click here for a full list of the seized websites.

The websites now display a banner announcing the domain name has been seized by U.S. Immigration and Customs Enforcement.

During "Operation In Our Sites," federal law enforcement agents purchased counterfeit NFL jerseys marketed as "authentic," knock-off sunglasses and electronics that were deemed illegal under trademark laws.

In most of the cases, according to ICE, the illegal merchandise was shipped to the United States by distributers in other countries.

Bill Vizas of Bill's Sports Collectibles in Denver says the fake NFL jersey market hurts his business.

"They sell them for one-half, one-third of what a regular retailer sells them for. Gives people the incentive for people to buy their Tim Tebow jersey for 30, 40 or 50 bucks instead of $75 to $200," Vizas said.

Vizas told 9Wants to Know that counterfeit jerseys are often lower in quality.

"Intellectual property crimes harm businesses and consumers," Attorney General Eric Holder said. "We have sent a clear message that the Department will remain ever vigilant in protecting the public's economic welfare."

During Cyber Monday in 2010, ICE seized 82 domain names.

(KUSA-TV © 2011 Multimedia Holdings Corporation)