Police found blood on the kitchen floor of the home of a Yale University lab technician charged with killing a Yale graduate student days before her wedding, according to search warrant affidavits released Wednesday.

Raymond Clark III sent e-mails to 24-year-old Annie Le "in the recent past," the affidavits said. Her e-mail address was found in a laboratory locker labeled "Ray," the documents said.

Meanwhile, an attorney for the fiancee of Clark says he's been told authorities are seeking a sample of her DNA.

Robert Berke, attorney for Jennifer Hramadka ,told The Associated Press on Wednesday that it's unclear why authorities want her DNA. He says he has been told she is not a suspect.

Berke says investigators have wanted to interview Hramadka, but the interview did not take place.

A prosecutor and police declined to comment.

The warrants in Clark's casedo not indicate the source of the blood found in Clark's apartment. Le's body was found stuffed behind a research lab wall in September on what was supposed to be her wedding day. Autopsy results show Le was strangled, but the motive remains unclear.

Clark has not yet entered a plea. His public defender, Joe Lopez, did not immediately return a phone call Wednesday.

SLIDESHOW: Yale Graduate Student Murdered

The affidavits show that police searched for evidence in Clark's home, two cars that he used and numerous lockers in the laboratory building where Le's body was found.

The suspect "has gone to great lengths to conceal evidence in multiple locations in unusual places," the affidavits said.

Two days before Clark was arrested, investigators said they found blood "in plain view" on the kitchen floor near the entrance to his apartment. Authorities took plastic door panels and carpeting with "blood-like stains" from the Taurus in which Clark was riding in the hours after Le's disappearance.

Investigators found a white rag, tweezers, scissors, a screwdriver and several plastic tubes in a clogged drain pipe in the building where Le's body was found, the affidavits said.

Portions of the affidavits released Wednesday were blacked out.

Police had previously revealed that they discovered other items linking Clark to Le's death, including a green-ink pen under Le's body with her blood and Clark's DNA. Police have said Clark signed into the secure building with a green pen on Sept. 8, the day Le disappeared.

They had also said DNA from Le and Clark was on a bloody sock found hidden in a ceiling. Elsewhere in the building, they found a pair of work boots labeled "Ray-C" that had blood-like stains on them, and a hospital scrub shirt with blood-like stains that was similar to the shirt Clark wore that day, police had previously said.

In arrest warrant affidavits released last month, Clark told investigators that he never socialized with Le or had contact with her outside of work. He told investigators that he knew Le for about four months, according to court papers.

Clark told police that Le left the building 15 minutes before him, carrying her notebook and two bags of mouse food. An extensive search of the crime scene failed to locate Le's notebook or her shoes.

Court papers previously released describe a bloody crime scene and Clark's efforts to scrub floors.

Investigators say Clark tried to hide a box of "Wipe-Alls" that later was found to have traces of Le's blood.

Clark was also seen by investigators scrubbing floors with SOS pads and cleaning solution even though the floor appeared to be clean, according to the affidavit. He was also spotted "on the floor" inside Le's lab scrubbing under a sink with a brush or cleansing pad, the affidavit said.

Investigators uncovered "a possible medium velocity blood-like spray pattern" on the wall that tested positive for blood and showed apparent efforts to clean the blood off the wall.

The blood at the scene suggests there was a struggle, experts said, noting the scratches on Clark's body and the surgical gloves Le was wearing that left her thumb exposed.