News has broken this afternoon that the Labour councillor for Mosborough has passed away.
She was responsible for parks and green spaces, sport and leisure, culture and the arts, library services and cohesion and community safety.
She was also the chair of the Police and Crime Panel for South Yorkshire.
No further information is yet available, but tributes have started pouring in.
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Simon Landau said: “A terrible shame. Isobel Bowler was one of our most talented and contributed so much in such a short time.”
Fellow councillor George Lindars Hammond said: “Devastating to hear of Isobel Bowler’s death. She was amazingly friendly, funny and talented and so kind to me when I was new in Sheffield.”
Coun Bowler was Cabinet Member for Neighbourhoods at Sheffield City Council.
University of Sheffield’s head of architecture Fionn Stevenson said: “This is absolutely tragic - Isobel was a beacon for culture in Sheffield. Huge loss!”
Gleadless Valley councillor Chris Peace added: “Incredibly sad that Isobel Bowler has passed away. She was my mentor when I was first elected. A lovely woman and inspiration to so many.”