We barricaded the door - Terror of Kiwi student caught in US college shooting

Alex Howe (right) has been a student at Delta State University in Mississippi for almost two years. Photo / Supplied via Facebook

A 20-year-old New Zealand student was in a classroom with a door barricaded closed while a history professor was shot dead at the university she attends in the United States.

Alex Howe of Ohope in the Eastern Bay of Plenty has been a student at Delta State University in Mississippi for almost two years. She has been studying exercise science and attends the American university on a tennis scholarship.

She has been enjoying the close-knit community at the university of fewer than 3000 students, but it all changed on Monday morning when a shooting occurred on the campus.

"It was the busiest part of the day... most students were in class [when it happened]," she said.

History Professor Ethan Schmidt, 39, had been shot and killed while he sat at his desk in a university office by a fellow teacher.

Shannon Lamb, a geography teacher at the university, was found dead from a self-inflicted gunshot wound on Monday night local-time.

He was also suspected of murdering Amy Prentiss, a woman detectives believe he was romantically involved in.

The university was in lock-down for three hours.

Students received alerts on their phones, and the university posted a message to its Facebook page when the shooting was reported.

"We were all on our phones and the teacher was saying 'put those away we need to finish the lesson' and someone said 'There's an active shooter'," Ms Howe said.

"Straight away the boys were putting things... barricading the door and pushing desks and chairs in the way... that was probably the scariest part."

Her friend and housemate was in the building next door to the shooting and heard the two loud gunshots.

Victim Professor Ethan Schmidt, right, and his alleged killer Shannon Lamb.

"Obviously people were texting around and trying to find out what was happening," she said.

"The hard thing was we didn't know what was happening, we didn't know who was in trouble and where the guy was... there were a lot of rumours."

Ms Howe said she was debating with herself whether to alert her parents in Ohope to what was happening from the classroom she was locked in.

When she sent a text message home, she wasn't expecting an immediate reply because of the time difference.

"Straight away [her mother] was like 'you're coming home now', she was freaking out. To make things worse, my phone went flat."

Police SWAT teams came to the classroom Ms Howe was in and banged on the door.

"We let them in and they were like 'everyone hands in the air'... we had to leave with our arms raised... it was really freaky."

Back at her home on campus, Ms Howe FaceTimed with her very concerned parents.

"They were absolutely freaking out, they were like 'you need to come home, this doesn't happen in our country'."

Despite the frequency with which college shootings happen in the United States, Ms Howe said she never imagined it would happen at Delta State.

"The whole community is in shock, especially because our school is so small and so close. Everyone knows each other, everyone's got a good bond with each other."

Classes have been cancelled today and Ms Howe said she had been staying at home and resting.

A candlelight vigil will be held tonight US time for the professor who was shot, and Ms Howe said she was looking forward to getting out of the house and seeing everyone in the university community come together.