STAR, N.C. — A disgruntled employee opened fire at a lumber company early today, killing three people and injuring another person before he went home and turned the gun on himself, leaving him wounded, authorities said.

The person injured at the McBride Lumber Co. in central North Carolina was flown to a hospital, Sheriff Dempsey Owens said. The gunman was also taken to a hospital.

Their conditions were not immediately available.

The shooter left a note, but police would not reveal what it said.

Owens said witnesses reported the gunman was a disgruntled employee, though it wasn’t clear what he was upset over.

The company’s founder, Dorothy McBride, said she was shocked.

“Oh, my God, I can’t believe it,” said McBride, who was not at the business at the time of the shootings. “I just can’t talk about it right now. I have to find out more.”

A family-owned business, the company makes pallets and treated wood for furniture and other products.