NEW HAVEN, Conn. — New Haven police said this morning have released a Yale University animal research technician they questioned in the killing of a graduate student after collecting DNA samples from him and searching his apartment.

Police department spokesman Officer Joe Avery said Raymond Clark left the station with his lawyer at about 3 a.m. today.

Clark has not been charged in the killing of 24-year-old Annie Le, whose body was found stuffed behind a wall Sunday in a Yale laboratory building where both she and Clark worked. Police are calling him a "person of interest."

Police took Clark into custody Tuesday night at his apartment in Middletown.