Two people were killed in an explosion Monday morning at a steel factory in the Pittsburgh area.
Officials said Monday night that a person who had been missing was confirmed dead.
“It is with profound sadness that I share with you that the U. S. Steel colleague who had been unaccounted for has been located and confirmed deceased, following an extensive search and rescue effort," David Burritt, the company's CEO, said in a statement.
At least 10 people were injured in the blast, officials said.
Five were in critical but stable condition Monday night, Allegheny County officials said in an update. Five people were taken to the hospital and were treated and released.
Officials said others had been injured and treated at the scene, but they did not provide a number.
Investigators are working to determine the origin and cause of the explosion, officials said.
"Obviously this is a tragedy we want to understand," said Scott Buckiso, Executive Vice President and Chief Manufacturing Officer for U.S. Steel
The blast ignited shortly before 11 a.m. between two batteries at Clairton Coke Works, officials said.
The U.S. Steel facility southeast of Pittsburgh annually produces millions of tons of commercial coke, a type of fuel used in a steel production.
The rest of the plant was stable, Buckiso said.
The county health department was also at the factory to monitor air quality, the spokesperson said in a statement.
Air quality monitors so far had not detected levels of potentially harmful gases and particulates that exceed federal standards, Allegheny County Executive Sara Innamorato told reporters.
But residents who live within a mile radius of the plant were advised to remain indoors, close all windows and set HVAC systems to recirculate "out of an abundance of caution," she said.
Clairton Mayor Richard Lattanzi said it was a sad day for the city and “a sad day for the steel workers.”
"These guys come to work and they put their gear on and they go to work to make a living for their family, not knowing if they’re going to make it home or not," he told NBC affiliate WPXI of Pittsburgh. "This is one of those situations."
Burritt said nearly 1,300 people work at the plant each day. It's the largest coke manufacturing facility in the country, according to the company's website.
United Steelworkers District 10 Director Bernie Hall said it has occupational health and safety experts at the scene.
“While we are still determining the scope of the tragedy, we are aware that multiple workers are receiving medical treatment for their injuries,” he said. “In the coming days, we will work with the appropriate authorities to ensure a thorough investigation and to see that our members get the support they need.”
In 2019, two environmental organizations and the Allegheny County Health Department sued U.S. Steel over what one of the groups described as a catastrophic fire and breakdown of pollution control systems at three facilities, including Clairton Coke Works.
U.S. Steel settled for $42 million last year, according to one of the one of the plaintiffs, Clean Air Council, agreeing to fund local public health projects and upgrade pollution control and plant reliability systems.
