Updated 02/15/12 - 8:02 p.m.
CHICAGO (CBS) -- Mayor Rahm Emanuel is losing his first major cabinet member. CBS 2 Chief Correspondent Jay Levine has learned that Fire Commissioner Robert Hoff is retiring.
Hoff was one of the few leftovers from the Daley administration. He submitted his resignation on Wednesday.
LISTEN: WBBM Newsradio's Bob Roberts reports
He will be replaced by former Office of Emergency Management and Communications boss Jose Santiago, who left OEMC to return to the Fire Department when Emanuel took over as mayor, in part because of problems during the Groundhog Day blizzard last year.
Hoff was one of the most respected firefighters ever to serve as head of the Fire Department. Sources said he's leaving for personal reasons and not because of any rift with Emanuel.
In fact, sources said, the mayor appeared at Fire Department headquarters Tuesday for the annual ceremonial bell-ringing to commemorate the death of Hoff's father, also a firefighter, who died in the line of duty 50 years ago.
WBBM Newsradio's Bob Roberts reports Hoff was himself hero firefighter himself before moving up to commissioner, winning the top department award for bravery in 1992 and 1997.
Chicago Firefighters Union Local 2 President Thomas Ryan said Hoff's credentials made him popular with the rank and file.
"He earned the respect of everyone on this job. You know, him and I were obviously were on different sides as commissioners, but all in all, I think he served the city proud," Ryan siad.
Santiago, like Hoff, is known as a fireman's fireman.
As one source said, get between him and a burning building and you're likely to get run over.
A formal announcement about the changes is expected on Thursday.
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