Central City, CO — The deaths of two Central City firefighters has been determined to be accidental carbon monoxide poisoning, according to a release from the Gilpin County Sheriff’s Office.

The couple, Cody Allen, 29, and his wife Shelby Allen, 27, were found dead in their Central City home, Friday morning, GCSO said.

Cody Allen started as a volunteer in July 2009 and had recently been hired as a lieutenant, according to GCSO. Shelby Allen worked as a volunteer with the department since February 2016.

GCSO said both Cody Allen and Shelby Allen grew up in Gilpin County.

“Our hearts and prayers are with the Allen Family, Central City Fire Department Family and our community at this devastating time,” GCSO said in the release.

The case is still under investigation by GCSO.