NEW HAVEN, Conn. -- Search warrant affidavits used by police investigating the killing of a Yale University graduate student were unsealed Wednesday morning.

Police used the warrants while investigating the killing of Annie Le, a 24-year-old graduate student from Placerville, Calif. Her body was found inside a wall at a Yale research lab in September on her would-be wedding day.

PDF: Raymond Clark Search Warrant

Authorities charged a technician at the lab, 24-year-old Raymond Clark III, with murder in connection with Le's death. Police said Le was strangled, but the motive remains unclear.

While most of the information revealed in the 70-plus page document has already been made public, several new details emerged.

Among the new details was that blood-stained clothes were found inside Clark's Middletown apartment. Investigators said sneakers, with unknown reddish stains were also found inside Clark's car.

"During the search of the residence, blood-like stains were located in plain view on the kitchen floor in close proximity to the entrance to the apartment," the warrant reads. "A presumptive test was conducted on the stain for the presence of blood which yielded a positive result."

According to the warrant, Le's e-mail address was found inside a locker labeled "Ray" at the Yale lab. Investigators said Clark had contacted Le via e-mail in the past. According to the warrant, Clark said he met Le sometime after the beginning of 2009. He said he never socialized with Le and that he never had contact with her outside of a work setting.

An investigator said he was told by Clark that Clark believed he was the last person to see Le before her disappearance, according to the warrant.

The warrant also details Clark's cleaning habits in the lab, behavior which was documented in a previously released document.

According to the documents, a graduate student first found a box of wet wipes with blood splatter on Sept. 10 at the lab where Le and Clark worked.

Members of the FBI were called to the laboratory after the wipes were found, police said. While a Yale University police officer waited for the FBI to arrive, Clark came in and out of the lab room several times, according to the documents. Police said Clark walked over to the wipes and moved the wipes from the far-left corner to hide the blood splatter when he thought no one was looking. After moving the wipes, Clark made small talk before leaving the room, police said.

A Yale University police officer said he thought Clark's cleaning was strange since the area was already clean.

Witnesses told police that they saw Clark scrubbing a floor in the lab under a sink near a drain, according to the documents. Clark later came back into the laboratory and began scrubbing the floor grate and drain with SOS pads and cleaning solution, according to the documents.

Investigators said a rubber glove and low-cut white sock were found in a drop ceiling located in a hallway outside the lab area. Police said both the glove and sock had blood and hair on them. They said they also found a pair of work boots and missing shoe laces and one blue, short-sleeved hospital scrub with blood-like stains on them. Police said video surveillance shows Clark wearing a similar shirt. According to the documents, the back of the work boots were labeled, "Ray C."

In the previously released arrest warrant, police said the evidence found in the ceiling matched both Le and Clark's DNA.

The search warrant also details evidence seized from drain pipes in the 10 Amistad Street building.

According to the warrant, "On Sept. 20, the night sanitation crew located a clogged drain at 10 Amistad ST. Animal Research Center. Members of the Major Crimes Squad Central division responded and eventually retrieved medical scrub tops stuffed into the drain pipe."

Police said investigators were called back to the building on Sept. 22 after more items were found stuffed in another drain pipe.

"Upon arrival, we were directed to the area in question and shown a large empty plastic bag, a white rag, tweezers, one scissor and several Eppendorf plastic tubes. These items were past the debris collection basket, which meant that in order to place these items int he manner they were found in the drain pipe, someone would have to remove the debris basket and discard said items into the drain pipe," the warrant reads.

The warrant also details both Clark and Le's use of their security key cards in the time surrounding Le's disappearance. According to the documents, Clark used his key card excessively around the time of Le’s death. Le used her card three times on Sept. 8, according to the documents. Her last entry to a room was recorded at 11:50 a.m. entering room G13. According to the documents, Clark used his key card 11 times on Sept. 8 in rooms G13 and G22. They said the week before, he entered those rooms an average of three times. Police said Clark is the only one to access G22 after Le went into room G13.

After looking at surveillance video, police determined Clark arrived for work on Sept. 8 wearing blue jeans, white shoes and a dark jacket with stripes. He was later seen entering the building after a break wearing blue scrubs with a red draw string, police said. When exiting the building after a fire alarm sounded, Clark was seen wearing blue scrubs with a blue drawstring, police said. At the end of the day, Clark was seen leaving with blue jeans a dark T-shirt, police said.

Clark has not yet entered a plea. His next court date is Dec. 21.