A worker who became trapped after an 11-story building collapsed at a shuttered coal plant in eastern Kentucky has died following a multi-day rescue effort to find the missing man, officials said.
His death comes two days after another worker who was also trapped in the rubble died, officials said.
The coal preparation plant in Martin County collapsed at approximately 6:30 p.m. ET on Tuesday, according to Kentucky Emergency Management.
Two workers became trapped "underneath multiple floors of concrete and steel," the agency said in a statement.
Rescue efforts had been underway since Tuesday night.
Emergency workers quickly located one of the workers -- identified by officials as Billy Daniels -- and spoke with him, though he died on Wednesday, Martin County Sheriff John Kirk said.
Rescuers attempted to free Daniels but were unable to before he died, Martin County Judge/Executive Dr. Lon Lafferty told reporters during a press briefing on Thursday.
The second worker -- identified as Alvin Nees -- could not immediately be located. Following a days-long rescue operation, Kentucky Gov. Andy Beshear updated on Friday that he died.
"This is a heartbreaking situation," Beshear said.
Beshear declared a state of emergency in Martin County to mobilize state resources.
Multiple agencies responded to the scene to assist in the rescue efforts, including the National Guard’s Special Tactics Squadron K-9 search dog unit.
Upward of 50 rescuers are on the scene, officials said Thursday.
"It's horrific," Lafferty said of the scene. "Very large structure that was collapsed in on itself."
"Tremendous amount of weight, tremendous amount of force, tremendous pile of rubble there now," he continued.
The two workers were helping demolish the building at the abandoned mine site on Wolf Creek, according to Lafferty. A crew was working on the ground at the time of the collapse, he said.
Lafferty was unable to confirm who employed the two workers.
MORE: Former Delta pilot indicted for allegedly threatening co-pilot with gun during flightLafferty said in a social media post early Wednesday that he declared a local state of emergency in Martin County to help access additional rescue resources.
State Sen. Phillip Wheeler, whose district includes Martin County, said he is "deeply saddened" by news of the deadly collapse.
"This incident is a stark reminder of the inherent risks in any job and the unexpected nature of tragedy," he said in a statement. "We are prepared to assist those affected by loss or injury and their families and the local government in any way we can."