By Aug 12 (AfrikTimes) – Multiple explosions on Monday at a U.S. Steel plant near Pittsburgh killed two people and injured 10 others, according to the company and local authorities.
The blasts occurred just before 11 a.m. ET (1500 GMT) at the Clairton Coke Works, part of a sprawling industrial complex along the Monongahela River. Firefighters battled flames and heavy smoke billowing from the plant, which is owned by U.S. Steel, a subsidiary of Nippon Steel (5401.T).
Initially, two people were reported missing. One was found and transported to a local hospital, Allegheny County Police Assistant Superintendent Victor Joseph said during an afternoon briefing. The other missing individual was later found deceased following an extensive search and rescue effort, U.S. Steel confirmed in a statement to Reuters late Monday.
No cause for the explosions has yet been determined. “The probe into the explosion will be a time-consuming technical investigation,” Joseph said.
David Burritt, president and chief executive officer of U.S. Steel, said the company is cooperating with local authorities to determine the cause of the incident. Pennsylvania Governor Josh Shapiro posted on X that multiple explosions occurred and that his administration was coordinating with local officials.
The plant, a massive industrial facility along the Monongahela River south of Pittsburgh, is considered the largest coking operation in North America and is one of four major US Steel plants in Pennsylvania.
“The scene is still active, and folks nearby should follow the directions of local authorities,” Shapiro wrote at the time when one employee was missing.
The severity of the injuries has not been disclosed, though several victims were reportedly taken to hospital burn units.
Clairton Mayor Rich Lattanzi described the day as “horrible” for the city, located about 20 miles (32 kilometers) south of Pittsburgh, long known as America’s Steel City.
U.S. Steel has produced steel in the region since the late 19th century. However, the industry has declined over recent decades, resulting in plant closures and restructurings.
In June, Nippon Steel, Japan’s largest steelmaker, completed its $14.9 billion acquisition of U.S. Steel after an 18-month process to secure U.S. government approval, which faced scrutiny due to national security concerns.
While air quality monitors did not detect a dangerous rise in sulfur dioxide after Monday’s explosions, residents within one mile of the plant were advised to remain indoors, close windows and doors, set HVAC systems to recirculate, and avoid activities that draw in outside air, Allegheny County Executive Sara Innamorato said.
Aerial footage of a reported explosion at US Steel Clairton Coke Works in Clairton, Pa., Aug. 11, 2025.
The Clairton Coke Works is the largest coke manufacturing facility in the United States, employing about 1,300 workers. It operates 10 coke oven batteries, producing approximately 4.3 million tons of coke annually.
Coke is produced by heating coal at high temperatures and is used in blast furnaces as part of the steelmaking process.
