DETROIT (WWJ) — Detroit police have a person of interest in the case of a city firefighter who was murdered in December.

The man was arrested on unrelated warrants, but police believe he may have information regarding the death of 59-year-old David Madrigal, whose body was found in his home by his son on December 21.

READ MORE: Michigan Matters: From Mackinac to Motor Bella, Major Events Return

The cause of death was determined to be blunt force trauma to the head.

Family members grew concerned after not hearing from Madrigal for days, so his son went to check on him and discovered his body on the floor of the home, according to police. It’s not yet clear how long Madrigal might have been dead.

READ MORE: Rolling Stone Magazine Named ‘Respect’ #1 Song Of All Time

Police say Madrigal’s safe was stolen along with his SUV, which was later found burned-out.

Friends say Madrigal was assigned to Engine 33 and had planned on retiring this June. Officials say Madrigal is the third firefighter to die since October.

MORE NEWS: Fourth Stimulus Check: Will You See Another Relief Payment Soon?

Officials are not releasing any more details about the person of interest.