Three workers remained hospitalized Sunday afternoon following an explosion at a Pueblo steel mill Saturday evening.

All three are in “stable” condition and “expected to survive,” David Light, EVRAZ Pueblo vice president of operations, told The Gazette. Two had been sent to the local Parkview Medical Center and another was transported to the burn center of Aurora’s Anschutz Medical Campus, he said.

“Our concern is with the members of our team who are injured and still at the hospital,” Light said Sunday afternoon. “Our thoughts and prayers are with them and their families.”

Of the 28 employees who fled the building Saturday evening, eight were counted as hurt and taken to the emergency room, including the three still hospitalized Sunday, Light said. He added that all walked or ran themselves to the evacuation staging area. He declined to provide details on injuries.

Neighbors reported hearing a loud boom sometime before 6 p.m. Around then, as dark dust and smoke billowed above the plant along Interstate 25, firefighters rushed to the scene, Gazette news partner KKTV reported.

“The explosion itself was pretty powerful, definitely,” Pueblo Fire Department Assistant Chief Keith Miller told the outlet.

Fire crews “took a look around to try to find as many victims as we could, to get ambulances lined up for them, and try to triage everyone and see what we had inside the building,” Miller said.

Water leaked into a furnace that was melting steel, Light said, resulting in the blast. The “root cause” of the event remained under an investigation that continued Sunday, he said.

Light said it was “too early” to speak on the integrity of the mill.

“I do know that everything is safe and secure,” he said. “There’s no risk of danger right now, and there shouldn’t be anymore.”

Pending the investigation, operations will remain on hold, Light said.