DIXFIELD – The Occupational Safety and Health Administration will investigate an accident at an Irving Forest Products lumber mill in Dixfield where a worker lost part of his right hand.

J.D. Irving spokeswoman Mary Keith said the 24-year-old man was flown to a Boston hospital early Tuesday and underwent at least 18 hours of surgery. She declined to identify the worker by name or his hometown.

Med-Care Ambulance Director Dean Milligan said the man suffered a partial amputation of four fingers and a thumb, all of which were recovered.

An OSHA spokesman says an inspector will be sent to the site to investigate.