BREEN TOWNSHIP — State fire marshals have been brought in to investigate the cause of a house explosion late Thursday morning that killed a Hardwood couple in Dickinson County.

Roy Kline, 78, and Maryann Kline, 66, were found dead after officers from the Michigan State Police Iron Mountain post were called about 9:50 a.m. Thursday to a home on Fordville Road in Hardwood, according to a news release from the MSP Iron Mountain post.

Breen Township lists the home at W491 Fordville Road East.

The cause of the explosion still has not been determined. Two state fire marshals have come from Lansing to assist in the investigation.

Troopers were assisted by NORDIC Ambulance, the Breen Township Fire Department and the Felch Township Fire Department.