Report: Yale Suspect Tried to Hide Blood

Updated 2:10 p.m. ET

Staffers in white lab coats reported to work Friday at the end of an extraordinary week at Yale University as a report surfaced detailing the DNA evidence that police say implicates a technician in the murder of a Yale graduate student.

A law enforcement official told The Hartford Courant that police investigating Annie Le's death found DNA evidence implicating Raymond Clark III in a ceiling and in the wall recess where her body was found.

The official spoke on condition of anonymity, and New Haven police wouldn't confirm the information to The Associated Press.

The official said Clark tried to hide blood-spattered equipment and cleaned up areas Le was in before she vanished Sept. 8. Her body was found five days later on what was to be her wedding day.

Police charged Clark, 24, with murder on Thursday, arresting him at a motel a day after taking hair, fingernail and saliva samples from him to compare with the evidence from the crime scene.

Bond was set at $3 million for Clark. He did not enter a plea.

A law enforcement official - who spoke to the AP on condition of anonymity because the investigation continues and many details remain sealed - said Yale workers told police that Clark was a "control freak" who clashed with scientists and their proteges in the lab where they both worked at the Ivy League school.

As for motive, some believe Clark may have gotten into a dispute with Le over lab procedures, CBS News correspondent Randall Pinkston reports. As an animal technician, Clark cleaned cages and fed the animals that Le and other researchers used. There are reports that Clark sent Le a text message requesting a meeting to discuss cleanliness of the cages - it appears the lab workers were continually reprimanding researchers about the lab rules, Pinkston reports.

Investigators haven't decided whether the theory will ultimately lead to a motive but don't believe they'll need to establish one when Clark goes to trial because of strong forensic evidence, the official said.

Authorities would not discuss a motive, largely because Clark has not been talking to police, the official said. They also would not disclose the DNA test results or how they connected Clark to the slaying.

Security guards continued their street patrols Friday morning and news crews set up for another day of staking out the college's medical complex. A makeshift memorial of candles and flowers was arranged at the entrance to a park across the street from the lab building, in an area of squat, utilitarian buildings about a mile from the majestic main campus.

Kristin Dugan, who works in the building where Le was found dead, said she did not fear for her safety there before Le's killing or afterward.

"Things happen; you can't stop evil," she said. "If evil's going to happen, it's going to happen anywhere."

Le's work at the university involved experiments on mice that were part of research into enzymes that could have implications for treatment of cancer, diabetes and muscular dystrophy, while Clark's technician job involved cleaning floors and mouse cages.

New Haven Police Chief James Lewis has called Le's death a case of workplace violence. He would not elaborate except to say reports that the two had a romantic relationship were untrue.

Appearing on CBS' "The Early Show" Friday, legal analyst Lisa Bloom said that prosecutors do not have to prove motive.

"It's not an element of murder or any homicide crime," she said. "Sure, they'd like to have it, because a jury is always going to be curious as to what the motive is. But when there's a mountain of physical evidence which sounds like what we're gathering here now, they certainly don't need to have motive."

More from the Crimesider blog on the investigation into Annie Le's murder:

Was Workplace Violence Behind Killing of Yale Student?
Did Clark Force High School Girlfriend to Have Sex?
Yale Suspect's Wedding Web Site Goes Dark
Photos: Who is Raymond Clark III?
Photos: Raymond Clark and Fiancée in Love
Photos: Yale Holds Vigil for Slain Student
Photos: Student Found Dead on Wedding Day

Clark appeared in court with two public defenders. Joseph Lopez, one of the defense attorneys, said he still was reviewing the case and declined to comment.

Two friends of Clark's since childhood, appearing on CNN's "Larry King Live" on Thursday night, said they were stunned by the murder allegations and could not reconcile them with the young man they've known for years.

"That's not the Raymond Clark I've talked to my whole entire life," Bobby Heslin said.

"I just can't picture him doing something like this," Maurice Perry said.

The New York Times reported that Clark at times grew angry if lab workers did not wear shoe covers. "He would make a big deal of it, instead of just requesting that they wear them," said a researcher who asked not to be identified.

ABC News reported that Clark sent a text message to Le on the day she vanished requesting a meeting to discuss the cleanliness of mouse cages in the research lab.

Reached at their homes after work Thursday, several of Le's co-workers at the lab declined to comment.

The Connecticut medical examiner said Wednesday that Le died of "traumatic asphyxiation," which could indicate a choke hold or some other form of suffocation caused by a hand or an object such as a pipe.

A memorial service is planned on Long Island sometime between the Jewish high holidays of Rosh Hashanah, which begins Friday evening, and Yom Kippur on Sept. 28, according to the temple attended by the family of Le's fiance, Jonathan Widawsky.

The temple "wants to create a private memorial service for them," said cantor Sandra Sherry of Temple Beth El in Huntington, N.Y.

Clark was being held Thursday night at the MacDougall-Walker Correctional Institution, a high-security facility in Suffield, about 20 miles north of Hartford. His next scheduled court date is Oct. 6.

More on the Annie Le investigation at CBSNews.com:

Yale Student Suffocated, Coroner Finds
"The Early Show:" Yale 'Unnerved' By Murder
Yale Student's Slaying an Inside Job?
Cops: Yale Student Killing Not Random Act
Tragic Find In Search for Yale Student