Craigslist, Classifieds or a Terror-fieds?

Philip Markoff, a 22-year-old medical student at Boston University School of Medicine, is being charged with his second criminal case today, according to CNN. The student was under police surveillance, and taken into custody after a traffic stop on Monday afternoon.

Julissa Brisman, a 26-year-old model from New York, was found unconscious with multiple gunshot wounds at Boston's Copley Marriott Hotel, where she was staying, on April 14. Brisman offered massages via Craigslist, an online classified ads service. This is where the killer is believed to have found the young woman.

It is believed that the encounter between Markoff and Brisman began as attempted robbery.

"It appears there was a struggle between the victim and the suspect in the threshold of the hotel room immediately prior to the shooting," said the Boston Police Department on their Web site.

He was previously involved in an armed robbery and kidnapping in a case involving another woman. Markoff allegedly robbed a 29-year-old woman at gunpoint, four days earlier, at a Westin Hotel in Boston.

As a result, Craigslist is now looking for ways to make it safer for their users.

"Anytime something like this happens, it's a wake-up call," said Craigslist CEO Jim Buckmaster.