09/16/2009 at 01:45 PM EDT
Yale graduate student Annie Le was officially ruled a homicide victim, dying of traumatic asphyxiation due to neck compression, the medical examiner said Wednesday.
Police in New Haven, Conn., took Raymond Clark III, 24, into custody
Tuesday in order to collect DNA samples from him, authorities announced. Police also collected items from the home Clark shares with his fiancée in Middletown, about 20 miles north of New Haven, before police released him early Wednesday.
Clark was not charged, nor was he officially named a suspect in the case. Le
, 24, a bride-to-be
was found dead in a building near the medical school on Saturday. Police did name Clark as a "person of interest," however.
Clark, who has been in the employ of Yale University for four years, worked in the basement where Le's body was found. According to reports, he failed an FBI lie-detector test and had scratches on his chest. A university source told the New Haven Register
that Clark and Le likely knew each other, because he cared for the mice she used in her experiments.