A Yale lab technician accused of strangling a graduate student had access to campus buildings, including the lab area where he is suspected of stashing her body, until he was arrested more than a week after she disappeared, a university spokesman said Monday.

Raymond Clark kept the identification card that allowed him to access the research building where 24-year-old Annie Le was killed, as well as other Yale buildings, even when investigators were following him around the clock, Yale spokesman Tom Conroy said.

Yale didn't disable the card until Clark was arrested Thursday at a hotel and charged with murdering Clark, Conroy said. It wasn't immediately clear why Yale let Clark retain his access privileges.

Police say Clark killed Le, a pharmacology graduate student who did research on the mice that it was Clark's job to care for, on Sept. 8. Her body was found five days later, on what was to be her wedding day, stuffed into a hidden wall recess in a laboratory where they both worked.

Clark was under constant surveillance even before Le's body was found and the case was ruled a homicide. Conroy wouldn't say whether Clark continued to work in the days before he was arrested.

New Haven police said Monday that they don't expect to make more arrests in Le's killing and rebutted media reports that police were considering whether Clark had an accomplice.

"It's still my belief I don't expect anyone to be charged," Police Chief James Lewis said. "But I don't know where the evidence may take us. No arrests are expected at this point."

Lewis confirmed that a car towed by police Saturday from the Cromwell, Conn., hotel where Clark was arrested belonged to his father, Raymond Clark Jr. Clark was either driving his father's car or was in it at some point, police spokesman Joseph Avery said.

An attorney for the younger Clark didn't return a call Monday.

Clark was arrested Thursday, a day after police promised to seek an arrest warrant as soon as a DNA match had been found. Police got a search warrant to force Clark to provide hair, fingernail and saliva samples on Wednesday.

Lewis said that the FBI interviewed Clark before he was arrested, but that local police did not because he had invoked his right not to talk.

Clark was an animal lab technician, cleaning floors and mouse cages in the lab where Le conducted research. Her team experimented on mice as part of research into enzymes that could have implications for treatment of cancer, diabetes and muscular dystrophy.

A law enforcement official told The Associated Press on condition of anonymity that co-workers described Clark as fastidious and territorial about the mice whose cages he cleaned. Police are investigating whether that attitude might have set off a clash between Clark and Le, originally from Placerville, Calif.

Le will be remembered Wednesday at a private memorial service at the temple that her fiance's family attends, said Rich Pilatsky, whose wife is the cantor at Temple Beth El in Huntington, N.Y.

Le's funeral is planned for Saturday at Holy Trinity Church in El Dorado Hills, Calif., said the Rev. Dennis Smith, acting as family spokesman.