For the second time this week, Westport police have charged a man with posting an ad to hire a prostitute on Craigslist, a classifieds website.

The man, 64-year-old Robert Eastright of Ludlow Avenue in Norwalk, was busted Friday in a sting set up by police detectives who responded to his Craigslist ad in which he allegedly sought to make a "donation" to a woman for sexual favors.

Contacted by a female detective, Eastright graphically described his sexual desires and what he was willing to pay, police said. A meeting was set up and when Eastright arrived with money in hand and confirmed to an undercover officer that he was the man who wanted to pay for her sexual services, he was arrested.

The latest arrest and the arrest Tuesday of a Bridgeport seeking to hire two prostitutes in exchange for drugs were prompted after Westport police launched an investigation into Craigslist classifieds when they received a complaint in early September about a "Casual Encounters" ad by a man seeking a woman to have sex in the Westport Library.

The man apparently felt the semi-private environs of the library would be a suitably erotic setting for public sex acts, police said. After police learned the man's identity and interviewed him, they determined that he never carried out his plans for sex in the library. He was not arrested, but was banned for life from library property.

During that investigation, police said in a statement that it became apparent the "Casual Encounters" section of Craigslist appears to be "an on-line red light district where people were openly soliciting sexual favors for not only monetary reward but also for narcotics."

Police also said in the statement, "It became evident that people are willing to enter Westport for the fulfillment of their sexual conduct and willing to not only pay for the indiscretion, but trade narcotics or possibly conduct lewd acts at establishments frequented by the community as a whole and especially children."

Detectives then contacted other people who posted ads on the site, setting up a sting operation targeting those they said were the most overt offenders.

On Tuesday, Casey Curtiss, 29, of Summit Street in Bridgeport, was arrested after police said he posted an ad seeking sex with two woman in exchange for drugs. He allegedly offered "Ecstasy" pills to pay for the prostitutes' services. When he arrived at the agreed meeting place in Westport, he allegedly showed the undercover officers the drugs and was then arrested on charges of two counts of patronizing a prostitute, possession controlled substance/hallucinogen and sale of hallucinogen/narcotics.

Sex ads on Craigslist have thrust the online classifieds site in the national spotlight lately when 21 state attorneys general, including Connecticut's Richard Blumenthal, pressured the site to remove its adult services section. The AGs have expressed concerns about human trafficking, child pornography and sexual exploitation resulting from those ads, according to a Blumenthal statement.

Blumenthal, who is running for the U.S. Senate, has been an outspoken leader of the AGs and Tuesday sent a letter to Craigslist CEO Jim Buckmaster asking for confirmation that the adult services portion of the site has been permanently shut down. Initially, the word "censored" appeared where the adult services listings had been, but the category more recently was entirely removed. Blumenthal also asked the business to actively prevent sex-for-hire ads from being posted on other parts of the website.

"There is the distinct danger and apparent trend that prostitution ads may migrate to other heavily trafficked portions of your site. Already, there are indications that the personals section may become rife with sexually graphic content and illegal activity, including prostitution," Blumenthal wrote in the letter.