CHARLOTTE, N.C. (CBS) — Two people were killed and four others wounded in a shooting Tuesday at the University of North Carolina-Charlotte, authorities said.

One person was taken into custody and there was no reason to believe anyone else was involved, police said.

As of Tuesday night, three students were in critical condition, UNC Charlotte campus police chief Jeff Baker said. Another student who was injured had less serious injuries.

The school remained on lockdown Tuesday night, Baker said.