One person has been confirmed dead and another remained trapped under debris early Wednesday afternoon after a defunct Kentucky coal plant collapsed on two workers Tuesday.

The incident happened just before 6:30 p.m. as the two men were salvaging material on the bottom floor, preparing the 11-story plant for demolition, authorities say. Both were buried under large chunks of concrete, steel beams and other debris, according to the Martin County Sheriff’s Office.

Although Sheriff John Kirk says first responders made contact with one of the men shortly after they arrived, it’s unclear whether they maintained contact with him. In an announcement made late Wednesday morning, Governor Andy Beshear said one of the men had been confirmed dead while the search for the other continued.