Charlotte, N.C. ? A Kannapolis, N.C., man is in jail after police say he used Craigslist to arrange for a man to rape his wife at the couple’s home while he watched.

The woman was sexually assaulted at knifepoint early Sunday, according to police. The couple’s two children were in the home, but unharmed and unaware of what was going on in their parents’ bedroom.

Police haven’t located or identified the armed assailant, and aren’t sure if he knew that the woman was not a willing participant. He may have thought he was fulfilling a fantasy for the couple, police told WCNC-TV, The Charlotte Observer’s news partner.

The incident was the latest garish headline for Craigslist, a San Francisco-based Web site featuring free online classified ads, whose sections devoted to personals and adult services have come under fire in recent months.

The Observer is not releasing the name of the man arrested in Sunday’s incident so as not to reveal the identity of the sexual assault victim. Police believe the husband arranged the assault without his wife’s knowledge or consent.

“When the victim woke up, she saw a male standing at the foot of the bed holding a knife,” Kannapolis Police Chief James “Woody” Chavis told WCNC.

The woman had no serious injuries, but she was taken to Carolinas Medical Center-NorthEast for an examination and an interview. Her husband was charged with first-degree rape, two counts of first-degree sexual offense and attempted first-degree sexual offense.

Authorities learned on Tuesday that the husband had responded to at least two personal ads on Craigslist, trying to arrange for someone to come to his house and “have sex with his wife using some type of scare tactic,” according to a Kannapolis Police news release.

Officers were called to the house around 2:45 a.m. after they got a call saying a man armed with a knife appeared in the couple’s home and sexually assaulted the woman. But investigators grew suspicious when they noticed there were no signs of forced entry. The stories the husband and wife told also had inconsistencies.

Craigslist has drawn increased scrutiny in recent months. In April, Philip Markoff was accused of killing a New York City woman who offered masseuse services through the Web site. Police have also accused the 22-year-old in the armed robbery of another woman. Police said both women had advertised erotic services on Craigslist.

The company has promised to eliminate the category and replace it with a new “adult services” section, where ads will be screened before they are posted.