Le's body was found Sunday, the day she was to marry a Columbia University graduate student. The 24-year-old doctoral student in pharmacology had been missing for five days when police found her remains stuffed behind a wall of a lab where she was doing research with animals. The New Haven Independent reported Monday that police, who had ruled out her fiance and a professor as suspects, were focusing on a lab technician who may have had romantic feelings she did not return. Two sources told the Independent that the technician had failed a lie detector test and had defensive body injuries. In an e-mail to reporters, Joe Avery, New Haven's police spokesman, did not rule out the possibility of a suspect. But all he said was: 'Just a note to clarify there are no suspects in custody and no students involved in this case.' But Avery did say that Le's slaying was not 'a random act.' Around the quads and the greens of the Ivy League school Monday, the undercurrent of fear was as palpable as the sense of mourning. In the evening, a few hundred students carrying candles gathered at a courtyard where undergraduates usually rush through on the way to classes. But on this occasion they paused to honor Le during an hourlong vigil with prayers, remembrances spoken by a friend, tears and a long moment of silence. As students began leaving, a violinist, sitting on a bench off to the side, began softly playing 'Amazing Grace.' The crowd paused to listen. Earlier, investigators continued to search for evidence in the building where Le's body had been found. The five-story, 120,000-square-foot building was closed. In the back, under a white tent, about 20 New Haven police investigators, many wearing protective suits, surgical masks and rubber gloves, could be seen sorting through huge bags and piles of materials that were taken from the building. Dogs were sniffing for evidence. According to an associate research scientist, who asked for anonymity because he was told not to talk to the media, the animals used in lab tests were kept in a highly secure area in the basement where he and Le worked. Access was limited to specific researchers, technicians and janitors. Not only are separate key cards required for the parking garage, main building and basement area, but 'each individual (basement) room has an additional key lock,' he said. 'Only the actual person doing the research has access. Not even professors (do).' The scientist, who had lunch with Le just about every day, said the crew was close-knit and that Le was a popular figure. Shawna Ueyama, 21, a child psychology major, said she was saddened by the death of a woman she did not even know. She kept getting worried phone calls from her mother, who lives in Japan. Late Monday, Ueyama was weighing whether to attend the vigil: 'I'd like to pay my respects and join the community, but I don't want to become that emotionally vulnerable.' Times staff photographer Carolyn Cole contributed to this report. 