CARY - An Illinois woman was charged with prostitution after undercover officers answered her ad on the Internet and arranged a meeting at the Red Roof Inn in Cary, according to police.

Officers also arrested Zachary Williams, 37, of California. Police described him as her pimp, and cited him with aiding and abetting prostitution and misdemeanor possession of marijuana.

"He rented the room and was the go-between for the compensation she received," said Capt. Michael Williams of the Cary police.

Williams said officers set up a meeting with Yvette Russell, 20, of Montgomery, Ill., on May 8 through her ad on www.craigslist.org. A policeman met her at the Red Roof Inn on Walnut Street near Crossroads and charged her with prostitution, Williams said.

Cary police found a small amount of marijuana, condoms and nearly $1,000 in cash when they arrested her, according to court records.

The day before the arrest, Red Roof Inn management contacted police about a man who had rented a room acting suspiciously. The motel staff told police that the man, Zachary Williams, had been in the hotel in the past, according to a search warrant made public Wednesday.

Motel staffers reported seeing a woman and various men coming and going from the room, according to the search warrant. One of the men asked the staff whether there was an ATM at the motel, according to the warrant.

Williams, the police captain, said his detectives have been using online sites such as Craigslist to investigate prostitutes, who use the sites to advertise.

Craigslist is an Internet clearinghouse that offers a vast variety of goods and services, including secondhand wheelbarrows, tennis rackets and baby gear.