The US Federal Trade Commission (FTC) building is seen in Washington, DC. The US Federal Trade Commission on Tuesday announced a crackdown on websites that sell acai berry weight loss products using fake endorsements from news sites such as CNN, Fox News and USA Today.

US regulators on Tuesday announced a crackdown on websites that sell acai berry weight loss products using fake endorsements from news sites such as CNN, Fox News and USA Today.

The US said it had asked federal courts to freeze the assets of 10 operations using "allegedly deceptive" tactics such as fake news websites to market their products.

The websites are designed to appear as if they are testimonials from legitimate newsgathering organizations.

"But in reality the sites are simply advertisements aimed at deceptively enticing consumers to buy the featured acai berry products," the FTC said.

"Almost everything about these sites is fake," David Vladeck, director of the FTC's Bureau of Consumer Protection, said in a statement.

"The weight loss results, the so-called investigations, the reporters, the consumer testimonials, and the attempt to portray an objective, journalistic endeavor," Vladeck said.

The sites often misleadingly include the names and logos of media outlets such as ABC, Fox News, CBS, CNN, USA Today, and Consumer Reports.

A photograph of photogenic French television presenter Melissa Theuriau is also frequently used to illustrate the sites although she has no affiliation with any of them.

The FTC said it has received numerous complaints from consumers who spent up to $100 for weight loss products after having been deceived by the sites.

It said it will ask the courts to force the the companies to provide refunds to consumers who purchased the supplements and other products.

The FTC said the defendants have likely received more than $10 million in ill-gotten commissions through the sites.