NEW HAVEN, Connecticut—Yale graduate student Annie Le died from traumatic asphyxiation due to neck compression, the office of the chief state's medical examiner said Wednesday.
Le's body was found Sunday in a university research building, five days after she disappeared.
"We took him into custody to gather evidence from his body and his person," Police Chief James Lewis said at a press conference.
New Haven police spokesman Joe Avery said Clark was released to his attorney this morning after he complied with requests for DNA samples. Avery did not know his whereabouts and said he was free to go wherever he wanted.
"We're committed to proceeding appropriately with the authorities with whom we are in regular communication," said David H. Dworski, Clark's attorney.
The public defender's office in New Haven is also consulting on the case.
Officers wearing gloves were seen entering and exiting Clark's apartment building Wednesday morning.
Lewis said that the warrants were for Clark's person and for Apt. 1A at 40 Ferry St. in Middletown. At 10:16 p.m., about 20 New Haven, state and federal law enforcement officers entered the apartment.
An unmarked police car pulled up to the apartment building's front door, and then officers escorted a man in a white T-shirt out of the building and placed him in their car.
Clark shares the apartment with his girlfriend, Jennifer Hromadka, whom he is engaged to marry in December 2011, according to the couple's wedding Web site.
Clark moved to Middletown from New Haven six months ago, where he shared an apartment with his girlfriend and three cats, according to former neighbor Taylor Goodwin, 16.
Lewis said that police have looked at 700 hours of videotape, interviewed 150 people and gathered 150 pieces of evidence in the case, some of which have DNA on them. He said that police are "trying to narrow down the list of suspects in this horrendous crime," and added that they haven't ruled out whether others were involved in the slaying.
When asked what led police to Clark, Lewis said, "We narrowed it down to who had access to this building and who was in what room and where."
Clark worked as an animal technician for the expansive Yale Animal Resources Center, which "provides for the daily care of all animals used in research at Yale (95 percent of which are rodents)," according to Yale University's website.
The center, which is accredited by the Association for Assessment and Accreditation of Laboratory Animal Care, coordinates the procurement of research animals, houses animals at multiple sites around the campus, and offers various scientific services to researchers, including breeding, tissue collection and analysis, animal restraint during experimentation and euthanasia.
In a recent school directory, the center had 67 people employed as animal technicians.
Le was asphyxiated and her body was stuffed into a barely 2-foot-long crawl space inside the laboratory where she had gone to work on the day that she disappeared, sources have told The Courant.
For days, investigators searched 10 Amistad St., a research building near Yale's medical school, looking for clues to what had happened to the petite, 24-year-old student who was supposed to have been married last weekend.