(CNN) — Four corrections employees were still being held hostage Wednesday hours after a standoff unfolded at a Delaware prison, according to the Delaware State Police.
A fifth employee, who was also taken hostage, was released around 2:40 p.m., about four hours after the hostage situation began at the James T. Vaughn Correctional Center in Smyrna, Delaware, said Sgt. Richard Bratz, a state police spokesman.
“We are doing everything we can to ensure the safety of everyone involved and using all of our available resources,” Bratz told reporters.
Bratz said the incident began around 10:32 a.m. when a corrections officer radioed for immediate assistance from inside a building that houses more than 100 inmates. Corrections officers responded and the facility was placed under lockdown, Bratz said.
That’s when the five employees were taken hostage, he said.
Bratz said the employee who was released was taken to a hospital with non-life threatening injuries.
It is unknown if there are any other injuries, said Bratz, but FBI and Delaware state police are continuing negotiations.
“It’s a very scary situation right now,” Geoff Klopp, president of the Correctional Officers Association of Delaware, said earlier during the standoff.
Citing the officers association, CNN-affiliate KYW said four guards and one counselor were taken hostage by inmates. One guard was released, the station reported.
The Kent County Fire Department responded to the prison around 11:30 a.m. after an alarm was sounded, KYW reported.
The correctional facility is about 90 miles east of Washington.
Built in 1971, it houses about 2,500 minimum-, medium-, and maximum-security inmates, including death row inmates, according to the state bureau of prisons.