A North Carolina state prison officer died Wednesday after being assaulted by an inmate.

Sgt. Megan Lee Callahan, 29, of Edenton, was attacked around 5:30 p.m. at Bertie Correctional Institute, and died about 6:20 p.m., officials said.

Authorities are investigating Craig Wissink in connection with her death, officials said. Wissink has been in prison for more than a decade after being convicted of first-degree murder in Cumberland County and sentenced to life in prison.

Callahan had been with the North Carolina Department of Public Safety since 2012. She was promoted to sergeant in February 2016, WNCN TV reports.