Retired Hibbing fire captain Steven J. Gillitzer died in a fire in Hibbing, Minn. on Tuesday, Dec. 27, 2017 Courtesy of Hibbing Fire Department

A Hibbing, Minn., fire that claimed several lives Tuesday took a heartbreaking turn on Wednesday when Hibbing authorities revealed that the deaths included a retired city fire captain, his wife and two of their grandchildren.

Steven Jon Gillitzer, 67, and his 63-year-old wife Patricia Lynn Gillitzer died at their home while attempting to rescue their grandchildren in 20-below temperatures, the Hibbing fire department said in a statement Wednesday. Nine-year-old Todd Jacob Gillitzer Jr., Jonathon Steven Gillitzer, 8, and 4-year-old Isaiah Atticus Adams were visiting their grandparents.

During the night "Gillitzer was alerted to the fire and rushed into action to save the family," the statement said, adding that the 8-year-old recalled being roused by his grandfather telling him there is a fire and they needed to get out. But the child couldn't find his way out of the home through the smoke and darkness.

Crews arrived on scene and rescued four victims from inside of the home, including two adults and two juveniles. Todd Jr. and Isaiah, who were being treated at Hennepin County Medical Center in Minneapolis, died because of the fire.

Gillitzer served as a Hibbing firefighter and paramedic for nearly 25 years before retiring in December 2000.

"This is a difficult time for our department and community as we rally together to work through this tragic event," the department said. "We continue to offer support and resources to the family and we continue to work though processing the scene to try and identify what caused this fire."

Correction (Dec. 29, 2017): This story has been updated with information from the Hennepin County Medical Examiner that corrects the middle name and age of Isaiah Atticus Adams.