There "may never be a clear answer" as to why a biology professor at the University of Alabama in Huntsville allegedly shot and killed three colleagues and wounded three others, campus police said Saturday in a news conference.
Amy Bishop, 42, was charged Friday night with one count of capital murder, which means she could face the death penalty if convicted, and authorities said Saturday more charges are pending. She reportedly had been involved in a tenure dispute on the campus.
Police said a 9 mm gun was found in a restroom in the science building on the University of Alabama's Huntsville campus, where the shootings occurred Friday afternoon.
Bishop, a Harvard-educated neurobiologist who became an assistant professor at the school in 2003, was taken Friday night in handcuffs to the county jail. As she got into a police car, she said, "It didn't happen. There's no way. ... They are still alive."
Students' assessments of Bishop varied. Some recalled an attentive, friendly teacher, while others said she was an odd woman who couldn't simplify difficult subjects for students. Sammie Lee Davis, the husband of a tenured researcher who was killed, said his wife had described Bishop as "not being able to deal with reality" and "not as good as she thought she was."
Davis said his wife was a tenured researcher at the university. In a brief phone interview, Davis 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.
University spokesman Ray Garner said that Bishop was up for tenure, but that the faculty meeting was not called to specifically discuss tenure.
Davis' wife, Maria Ragland Davis, was among those killed, along with Gopi K. Podila, chairman of the biological sciences department, and another faculty member, Adriel Johnson.
Bishop had created a portable cell incubator, known as InQ, that was less expensive than its larger counterparts. She and her husband had won $25,000 in 2007 to market the device.
Andrea Bennett, a sophomore majoring in nursing and an athlete at UAH, said a coach told her team that Bishop had been denied tenure, which the coach said may have led to the shooting.
Bennett 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."
Amanda Tucker, a junior nursing major from Alabaster, Alabama, had Bishop for anatomy class about a year ago. Tucker said a group of students complained to a dean about Bishop's classroom performance.
"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," Tucker said.
However, UAH student Andrew Cole was in Bishop's anatomy class Friday morning and said she seemed perfectly normal.
"She's understanding, and was concerned about students," he said. "I would have never thought it was her."
Nick Lawton, 25, described Bishop as funny and accommodating with students.
"She seemed like a nice enough professor," Lawton said.
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 will remain closed next week, and all athletic events were canceled. The wounded were still recovering in hospitals early Saturday. Luis Cruz-Vera was in fair condition; Joseph Leahy in critical condition; and staffer Stephanie Monticello also was in critical condition.
It's the second shooting in a week on an area campus. On Feb. 5, a 14-year-old student was killed in a middle school hallway in nearby Madison, allegedly by a fellow student.
Mass shootings are rarely carried out by women, said Dr. Park Dietz, who is president of Threat Assessment Group Inc., a Newport Beach, California-based violence prevention firm.
A notable exception was a 1985 rampage at a Springfield, Pennsylvania, mall in which three people were killed. In June 1986, Sylvia Seegrist was deemed guilty but mentally ill on three counts of murder and seven counts of attempted murder in the shooting spree.
Dietz, who interviewed Seegrist after her arrest, said it was possible the suspect in Friday's shooting had a long-standing grudge against colleagues or superiors and felt complaints had not been dealt with fairly.
Gregg McCrary, a retired FBI agent and private criminal profiler based in Fredericksburg, Virginia, said there is no typical outline of a mass shooter but noted they often share a sense of paranoia, depression or a feeling that they are not appreciated.
The Associated Press contributed to this report.