Police released a surveillance camera photo on Wednesday showing a man walking in the lobby of the Marriott Copley Place hotel while typing on a Blackberry the previous night, around the same time a New York City woman was found dying in the hotel.
Investigators said the man was "a person of interest" in the case.
"What we believe is that there are a series of independent operations that are occurring, and it’s very difficult for the hotels to police them because they don’t know who it is that’s coming in to use their rooms," Boston Police Superintendent Edward Davis told The Boston Globe. "We've been monitoring it very closely, but it's very difficult to completely eliminate it."
Police said 26-year-old Julissa Brisman of New York City was found with multiple gunshot wounds to the torso, Davis said. She was rushed to Boston Medical Center where she was pronounced dead.
Davis said police believe Brisman was a victim of an attempted robbery.
Police said the same man was photographed Friday at the Westin Hotel in Boston, where a 29-year-old Las Vegas woman was found bound and robbed.
Investigators said both victims offered massage services on the Craigslist.org Web site.
A massage table was found set up in Brisman's room. Authorities believe she had been in a struggle at the door of her 20th-floor hotel room before she was shot.
Lucy Slosser, a spokeswoman for the Marriott Copley Place, said the hotel has beefed up security following the shooting.
"We haven't seen an increase in crime at the hotel, so we believe this to be an isolated incident," Slosser said.
Slosser said the hotel was not fully occupied Tuesday night.
PICTURES of the Alleged Killer from the BOSTON GLOBE
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Thanks to OneofSeven for this tip!