A coroner says a worker at a north Mississippi plywood mill died after a piece of machinery malfunctioned.

Brandon Foster was killed Tuesday at Winston Plywood & Veneer in Louisville.

The 21-year-old died from massive head trauma and fractures to the face and neck, Winston County Coroner Scott Gregory told WTVA-TV.

Gregory had initially described the fatal incident as an explosion. Thursday, he said the chipper came apart.

The state medical examiner’s office is conducting more tests.

“Winston Plywood is devastated by the loss of our friend and colleague as a result of this accident,” said the company’s chief executive officer, Bruce Warren.