In 2016, Texas and California authorities raided the company's Dallas headquarters and arrested chief executive Carl Ferrer and other former company executives on pimping-related charges. The Justice Department has said it will provide more information on the action at 6PM EST on Friday. The company shuttered its adult section past year in response to government pressure.
CoStar, a US company that runs Apartments.com, accidentally uncovered in July of a year ago that Backpage had used a Philippines-based company named Avion to grow business in overseas sex trade.
Online ads for adult content have been under fire recently, following the passing of the bipartisan Stop Enabling Sex Trafficking Act.
Backpage experienced a 50% growth in ad volume within two months of Craigslist closing its adult section, according to an internal history of the company included in the Senate report.
Sen. John McCain, R-Arizona, said in a statement Friday that the apparent seizure of the website "marks an important step forward in the fight against human trafficking". 7 people have reportedly been charged, and local CBS affiliate 3TV/CBS5 reports that the Federal Bureau of Investigation have raided the Arizona home of founder Michael Lacey.
Suspects in Concord robbery arrested, police say
Officers noticed that the man was bleeding from his nose and mouth area and was very fearful, according to court documents. Authorities were already on the scene and the situation was still developing, police reported in the message.
She said the crackdown goes beyond Backpage, saying, "it's all major escort advertising sites that are being affected, we are going to experience rape and violence".
A representative from Backpage could not be reached for comment on Friday. A Phoenix FBI official said there was "law enforcement activity" at Lacey's home, but referred further inquiries to the Justice Department.
In the documents surrounding the backpage.com shutdown, there is information from 17 victims who all claim they were forced into sex trafficking - with some of them being children.
Backpage has affiliates across the country and around the world, and by 2014 brought in annual revenue of $135 million, the New York Times has reported.
A federal judge in Boston last week ruled that a lawsuit against Backpage could continue because it was shown the site had edited an advertisement.