Nearly three dozen johns and prostitutes were hauled out of hotels and motels in Warren this week as police began a crackdown on human sex trafficking in the city.

Seventeen women and 18 men from across metro Detroit were arrested during the first phase of Operation Crusade — from communities as far away as Farmington Hills and Bellevue and as close as Detroit and Roseville.

The three-day sweep started Tuesday and ended Friday morning and involved undercover male and female officers, Police Commissioner Bill Dwyer said. One private residence in the city also was involved in the sweep.

Dwyer said 75 charges — 30 felonies and 45 misdemeanors — have been filed, including transporting a prostitute and accepting earnings of a prostitute, which he said are 20-year felonies. Other charges include solicitation and use of a computer in the alleged crimes.

Police also seized drugs, including crack cocaine, cocaine and heroin, he said. Two women came forward as victims and have not been charged in the sting targeting what Dwyer said is "modern-day slavery."

"Our goals are to arrest, convict those persons who are responsible and to work with the victims," said Dwyer, who said intelligence was gathered for the next phases of the campaign.

Dwyer said Michigan has the 11th highest call volume to the National Human Trafficking Hotline in what is a nationwide epidemic that is a "billion-dollar industry" and involves young children. No minors were arrested during the Warren sting, authorities said.

Mayor Jim Fouts said the women arrested were addicted to drugs. He called the sting a "step in the right direction to have a clean and safe city," not only in the neighborhoods, but also at the hotels.

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Police Detective Craig Bankowski said he refers to the victims as "survivors. They survive every day."

He said the hotels and motels have been cooperative with police, which Dwyer said has been developing this campaign for a couple of months.

Bankowski said these types of investigations are "ever-changing" with technology, the internet, and social media platforms and apps that can solicit and recruit; money can pass hands in the form of e-money, including preloaded cards.

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Contact Christina Hall: chall@freepress.com. Follow her on Twitter: @challreporter.