Updated at 12:36 a.m. ET
A biology professor at the University of Alabama's Huntsville campus was charged with murder late Friday in the shooting deaths of three fellow biology professors at the campus.
Authorities say Amy Bishop, an instructor and researcher at the university, opened fire during an afternoon faculty meeting, killing the three and injuring three other school employees. Bishop has been charged with one count of capital murder, which means she could face the death penalty if convicted.
Bishop was taken Friday night in handcuffs from a police precinct to the county jail and could be heard saying, "It didn't happen. There's no way .... they are still alive."
Police said they were also interviewing a man as "a person of interest."
Several sources told CBS News affiliate WHNT-TV in Huntsville that after being denied tenure in the morning, the suspect walked into a biology department faculty meeting Friday afternoon and opened fire.
University spokesman Ray Garner said the three killed were Gopi K. Podila, the chairman of the Department of Biological Sciences, and two other faculty members, Maria Ragland Davis and Adriel Johnson.
Two others are in critical condition, and a third who was wounded was upgraded to fair condition. The injured were identified as department members Luis Cruz-Vera, who was listed in fair condition and Joseph Leahy, in critical condition in intensive care, and staffer Stephanie Monticello, also in critical condition in intensive care.
No students were harmed in the shooting.
Sammie Lee Davis said his wife, Maria Ragland Davis, was a researcher who had tenure at the university.
In a brief phone interview, he said he was told his wife was at a meeting to discuss the tenure status of another faculty member who got angry and started shooting.
He said his wife had mentioned the shooter before, describing the woman as "not being able to deal with reality" and "not as good as she thought she was."
Bishop, a neurobiologist from Harvard University, joined the UAH biology faculty as an assistant professor in fall 2003.
Bishop and her husband placed third in a statewide university business plan competition in July 2007, presenting a portable cell incubator they had invented. They won $25,000 to help start a company to market the device.
Amanda Tucker, a junior nursing major from Alabaster, Ala., had Amy Bishop for anatomy about a year ago. Tucker said a group of students went to a dean complaining about Bishop's performance in the classroom, and Tucker signed a petition complaining about Bishop.
"When it came down to tests, and people asked her what was the best way to study, she'd just tell you, `Read the book.' When the test came, there were just ridiculous questions. No one even knew what she was asking,"' said Tucker.
Andrea Bennett, a sophomore majoring in nursing, was in one of Bishop's classes Friday morning.
Bennett said nothing seemed unusual, but she described Bishop as being "very weird" and "a really big nerd."
"She's well-known on campus, but I wouldn't say she's a good teacher. I've heard a lot of complaints," Bennett said. "She's a genius, but she really just can't explain things."
Bennett, an athlete at UAH, said her coach told her team Bishop had been denied tenure and that may have led to the shooting.
"She went to Harvard, so she is very smart. I can see that her getting denied tenure at UAH would be pretty upsetting," said Bennett.
At one time, Huntsville Hospital was told to expect as many as 10 victims, WHNT-TV reports.
Nick Lawton, the son of a biology professor at the school, said his father was not among the victims, but he did not know much more.
Lawton, 25, was exercising when a friend phoned him to tell him about the shooting. He called his father, Robert Lawton, and found out that he was not hurt, then he let rest of his family know.
"All I know is that my father is OK," Nick Lawton told The Associated Press.
Sophomore Erin Johnson tells The Huntsville Times a biology faculty meeting was under way when she heard screams coming from the room.
The shooting happened Friday afternoon in the university's Shelby Center, a science building. University police secured the building and students were cleared from it.
Alabama Sen. Richard Shelby, for whom the center is named, released a statement to WHNT-TV about the shooting.
"I am deeply saddened to hear of this horrible tragedy. My thoughts and prayers are with the faculty and staff of the University of Alabama-Huntsville," the statement reads.
The Huntsville campus has about 7,500 students in northern Alabama, not far from the Tennessee line. The university is known for its scientific and engineering programs and often works closely with NASA.
The space agency has a research center on the school's campus, where many scientists and engineers from NASA's Marshall Space Flight Center perform Earth and space science research and development.
The university posted a message on its Web site Friday afternoon telling students the campus was closed Friday night and all students were encouraged to go home. Counselors were available to speak with students.
Garner said the campus was closed while police gathered evidence. He said at a news conference that the shooting was not unlike one the area experienced a week ago, when a 14-year-old student was shot to death in a middle school hallway, allegedly by a fellow student.
"This town is unaccustomed to shootings and multiple deaths," he said.
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