SMYRNA, Del. (AP) — Before he died, held in a closet by inmates at Delaware’s largest prison, Sgt. Steven Floyd saved the lives of fellow officers when he called out and warned his would-be rescuers that the inmates had set a trap, the head of the state corrections officers’ union said.

“Even in his last moments as the inmates attempted to take over the building, Sgt. Floyd told a couple of lieutenants to get out of the building and that it was a trap,” union President Geoffrey Klopp said.

Floyd was found dead early Thursday after authorities used a backhoe to smash through a barricade of footlockers and end a nearly 20-hour hostage standoff at the prison. A second hostage, a female counselor, was rescued minutes after tactical teams forced their way into a building at the all-male, 2,500-prisoner James T. Vaughn Correctional Center.

Delaware Gov. John Carney called the uprising a “torturous” ordeal. In a statement, he said authorities will hold accountable those responsible and “make whatever changes are necessary to ensure nothing like it ever happens again.”

Authorities did not immediately explain how Floyd died. They have said the inmates used “sharp instruments” to seize Building C and hold the 47-year-old hostage along with two other prison guards and a counselor.

Klopp said inmates staged a fight to lure Floyd, who radioed for help. They then turned on him, forcing him into the closet.

The inmates eventually released two hostages and got authorities to turn the water back on, saying they needed it for drinking and washing. Instead, they filled up metal footlockers and built barricades.

Klopp said the footlockers were used to hold inmates’ belongings. “Footlockers are a necessary evil in prison,” he said. “You’ve got to have some place to store and transport their personal belongings.”

During negotiations conducted via an officer’s walkie-talkie – which were broadcast online for more than an hour before officials blocked the transmission – the mediator tried to coax an unidentified inmate into letting him talk to Floyd to make sure he was OK.

The inmate responded that the negotiator could only talk to Floyd once the inmates got to talk to the governor. He told the negotiator that the prisoners wanted a “formal apology” from Carney for “decades of oppression.”

Floyd, a 16-year veteran with the prison, is the first Delaware corrections officer to be killed, according to Klopp.

The union president described Floyd as a wonderful husband and correctional officer who went the “extra mile for any human being he could help.” Last year, he received the warden’s award for outstanding performance.

An AP reporter who visited Floyd’s house earlier Thursday was told the family had been through a lot and did not want to speak.

Dave Dowty, a retired court-transportation worker for the Department of Correction, said he occasionally worked with Floyd.

“I just know he was a pretty good guy. He was quiet, professional,” Dowty said in a telephone interview.

Former Vaughn Correctional Center inmate Kendall Guinn, of Dover, had a low opinion of Floyd.

“He harassed inmates. He’s been doing it for years,” Guinn said in a telephone interview.

The others guards who were taken hostage were beaten severely by their captors and suffered broken bones, cuts and eye injuries, Klopp said. Authorities said their injuries were not life-threatening.