The Jessica Ennis-Hill gold postbox in Sheffield city centre was set alight over the weekend.
Flames were spotted in the post box in Barker’s Pool at 6.10pm on Saturday and staff from the nearby Lloyds Bar extinguished them.
The post box was painted gold after heptathlete Ennis-Hill won gold in the 2012 London Olympic Games.
In the first few weeks after the Sheffield-born athlete won gold people from all over Sheffield and further afield had their photographs taken next to the postbox.
Anyone with information should call South Yorkshire Police on 101.