Former Boston University medical student Philip Markoff, center, stands with his attorney during his arraignment Monday, June 22, 2009, in Boston.
(AP Photo/Bizuayehu Tesfaye)
BOSTON(CBS/ AP) The former medical student accused of killing a 25-year-old masseuse he met through Craigslist pleaded not guilty Monday to first-degree murder charges.
Philip Markoff was arraigned in Suffolk Superior Court. He was indicted by a grand jury Thursday after a two-month investigation.
Suffolk County District Attorney Daniel Conley told CBS's The Early Show that Markoff's fiancée, Megan McCallister, has been cooperative, but declined to say whether she would be a witness for the prosecution.
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PREVIOUSLY ON CRIMESIDER
June 22, 2009 - Accused Craigslist Killer In Court
May 19, 2009 - "Craigslist Killer" Set To Appear In Boston Court This Week