Clark, who was charged with Le's murder, had worked in the lab with Le where he performed maintenance duties, including feeding and cleaning the cages of mice Le used in her research.
While authorities waited for officers from the FBI to arrive to look at the box of blood spattered wipes, Clark entered the lab and shifted the box so the blood would not be in plain view.
Clark then proceeded to stand in front of the cart where the wipes were placed and make small talk with one of the officers, a move noted in the documents to be a "deliberate attempt by Clark to block her view of the box in question."
Later that day, Clark came back to the lab and "began scrubbing the floor grate/drain with SOS pads and a cleaning solution," according to the warrant. The officer in the room noted that it was "unusual" that Clark was scrubbing the drain because it "did not appear to need cleaning." Other officers also reported seeing Clark scouring the area underneath the sink that also appeared to be clean.
A lab coat marked "XL" with "red-colored stains" was also seized that same day in a nearby recycling box by authorities.
Using a DNA sample from Le, authorities matched the blood on the box of wipes to the victim.
Investigators spoke to Clark, who they say approached them, and told officers that he had only known Le for four months and that he had seen her leave the building on the day she went missing 15 minutes before him and before a fire alarm cleared the building.
Clark also told investigators that the scratch on his face and bicep was from one of his cats, according to the documents.
Investigators found a rubber glove with blood-like stains, a sock with hairs and blood inside a drop ceiling that was in the hallway outside the lab area where the two worked. A pair of boots labeled "Ray-C" was also found in the area.
Chemical analysis uncovered "blood-like stains that had been cleaned off" in one room, and a "possible medium velocity blood-like spray pattern on the wall" in another that the accused murderer had "attempted to clean.
On Sept. 13, investigators inspected the locker room near the lab and discovered "an odor similar to that of a decomposing body," which led them to the lifeless body of Le hidden in the wall behind the toilet.
Upon removing the panel of the mechanical chase -- a hollow section of the wall -- investigators "observed blood-like smears throughout the opening, behind the door frame, on pipe insulation and the access panel. Insulation had been removed from the inside of the wall to make room for Le's body, according to the documents.
Details of how Le's body was found are redacted in the warrant, other than the victim was found wearing surgical rubber gloves on both hands, with only her left thumb exposed. Along with Le's body, a green ink pen, stained lab coat and a sock were also found in the wall cavity.
A colored bead and a broken string were also found on Le's clothing. A similar bead was found in the lab during the investigation.
Surveillance video showed Clark changing his clothing several times on the day Le was murdered – noticed only by the fact that the color of the draw string on his scrubs changed between the time he entered the building to when he left. Bloodied scrubs were found with Clark's boots, according to the documents.