One male prison officer is dead and a female colleague has been hospitalized after they were held hostage overnight by inmates at a prison in Delaware, state officials said on Thursday (February 2).

The hostages were removed by police at about 5 a.m. local time from James T. Vaughn Correctional Center, a men's prison in the town of Smyrna, where an uprising began midday on Wednesday.

The incident, which prompted a lockdown of prisons statewide, started at about 10:30 a.m. on Wednesday when a correction officer radioed for help from the C building, which houses more than 100 inmates.

Inmates had been demanding better conditions and wanted to speak with senior officials, the News Journal of Delaware reported, citing phone calls with people inside the prison that were relayed through prisoners' relatives.

The prison, 40 miles (64 km) south of the city of Wilmington, holds about 2,500 inmates, including some with death sentences, according to the prison's website.