While details are still sparse, news is slowly being released about what exactly happened in a Delaware men’s prison where four Department of Corrections officers were held hostage and one was killed. 

After receiving a call for help late Wednesday morning, four officers entered Building C of the largest men’s prison in the state and were taken hostage by prisoners. Throughout the day, two of the guards would be released as well as 27 inmates who were also in the building, according to the New York Times.

As police officers surrounded the building on Wednesday, the prisoners made their demands. CNN reports that they demanded better prison conditions such as education and rehabilitation programs and better training for the guards who oversee them on a daily basis. Complaints about the living conditions in the James T. Vaughn Correctional Center in Smyrna have reportedly increased in the past year.

A former inmate told the Times that the hostage situation was likely the result of a buildup of tensions finally bubbling to the surface. And, Stephen Hampton, an attorney who has represented inmates at Vaughn, said that some even take plea deals just to avoid strict rules that deprive pretrial inmates of any socialization or resources.

Police eventually gained access to Building C where they found one of the hostages unresponsive. The still unnamed officer was pronounced dead at 5:29 a.m.

“This was a long and agonizing situation,” said Gov. John Carney in a statement. “Our priority now will be to determine what happened and how this happened. We will hold accountable anyone who was responsible. And we will make whatever changes are necessary to ensure nothing like it ever happens again.”