A professor was shot to death at Mississippi’s Delta State University on Monday — and the campus remained on lockdown as police searched for a “person of interest” who is also a professor at the school.

Authorities were searching for Shannon Lamb, 45, after Dr. Ethan Schmidt was found fatally shot in his office at Delta State Monday morning, said Cleveland Police Department Chief Charles Bingham. No students were injured, according to police.

Police first named Lamb, who is listed on the school’s website as a geography instructor, as a “person of interest” but later identified him as a suspect in the shooting.

Investigators believe Lamb might be in a 2011 black Dodge Avenger with the license plate number STF015, and asked anyone who saw Lamb or the car to call police because he is considered armed and dangerous.

Bingham said Lamb could have been involved in a homicide earlier Monday in the town of Gautier, which is about 300 miles south of Delta state.

Police hadn’t determined a motive for the campus shooting, Bingham said.

The school’s website lists the victim, Schmidt, as a professor of American history.

The school remained on lock down Monday afternoon, even though investigators had swept each building and believed Lamb had left campus, Bingham said.

But, he added, “We’re not taking anything lightly.”

A post on the school’s Twitter page at about 10:45 a.m. local time said: “An active shooter has been spotted on campus near Jobe Hall. Please take immediate lock down action.” Students and staff were also urged to stay away from windows.

Hundreds of officers from Mississippi Highway Patrol, Cleveland Police, Bolivar Sheriff’s Department and the ATF responded to the scene.

Delta State later tweeted that police were clearing all campus buildings.

Students and staff could be seen spilling on to the streets on the outskirts of campus at about 1:30 p.m. Many were led into the Walter Sillers Coliseum, about a block away from the school. School officials said they were sending food, water and counselors to the arena.

Classes will be cancelled today and tomorrow, including night classes. Counselors will be here tomorrow at 10 a.m. and 1 p.m. for groups. — Delta State (@DeltaState) September 14, 2015

The nearly one dozen schools within the Cleveland School District were also placed on lockdown as a precaution, a district spokeswoman said.

Delta State classes were canceled through Tuesday, but counselors would be on campus on Tuesday, according to a statement from the school.

Taylor Blue, a freshman at the school, said she woke up Monday to a text message saying the school was on lockdown.

“I was scared to death,” Blue, 18, told NBC News. She said she thought the campus was safe. “It’s such a homey atmosphere, and I never thought this would happen,” she said.

Blue was still on lockdown in her dorm room at 1 p.m. Monday, and said she didn’t know where her roommate was. She said she was relieved that she was able to let her family know she was unharmed right away.

“My mom called me in a panic. My sister called me hysterically crying,” Blue said. “My entire family is really worrying right now.”

More than 4,000 students attend the university, which is near the Arkansas-Mississippi border.

“We are grieving on this campus with this loss, and our condolences are with the family at this time,” Michelle Roberts, the vice president of university relations, said in a statement.

Delta State English professor Don Mitchell said Schmidt was “a wonderful family man.”

“He was a great scholar, a great friend and a gentleman in every sense of the word,” Mitchell told NBC News. “We are heartbroken, especially for his family and three children.”

“He’s just the all-around good guy,” said Schmidt’s aunt, Barbara Schmidt Unruh, from the professor’s hometown of Peabody, Kansas. “He was the best family man I have ever known,” she added. “He would do anything for his family.”

This story originally appeared on NBCNews.com

