Boston ? Philip Markoff seemed to have a good life: The handsome, clean-cut, 23-year-old medical student was planning a lavish beachfront wedding this summer to a beautiful woman.

But authorities say his computer and surveillance video paint a picture of a suspected serial criminal who targeted women offering erotic services through Craigslist. Now he’s accused of killing one and suspected of robbing and tying up another. And police have said there could be more victims.

“This was a brutal, vicious crime — savage, and it shows Philip Markoff is a man who is willing to take advantage of women, to hurt them, to beat them, to rob them,” District Attorney Daniel Conley said Tuesday. “He probably thought he was going to get away with it. He thought he was too smart for us.”

Authorities refused to comment on reports that Markoff might have been seeking money to pay gambling debts, but a Connecticut casino confirmed it was cooperating in the investigation.

Markoff, a second-year medical student at Boston University, appeared in court Tuesday on charges including murder, kidnapping and armed robbery. Dressed in a wrinkled button-down shirt and khakis, he said nothing during the brief hearing and was jailed without bail.

Defense attorney John Salsberg said later that Markoff is not guilty of the charges and “has his family’s support.”

Markoff is accused in the death of Julissa Brisman of New York City, who was found dead April 14 in a Boston hotel after being bashed in the head and shot three times.

Brisman, 26, was an aspiring model and actress who had advertised erotic massage on Craigslist. Authorities said she and Markoff communicated through e-mail and cell phone to set up a meeting.

Investigators traced an e-mail to Markoff, who created a new address the day before Brisman’s body was discovered at the Marriott Copley Hotel. He was arrested Monday in Walpole, less than 20 miles southwest of Boston, as he drove with his fiancee to Foxwoods Resort Casino in Connecticut.

Authorities say he was the man seen on surveillance video near where Brisman was found and where a woman was robbed in Rhode Island.

His fiancee, Megan McAllister, insists police have the wrong man.

“He could not hurt a fly,” McAllister said in an e-mail to ABC’s “Good Morning America. “All I have to say is Philip is a beautiful person, inside and out.”