Ceremonial jewellery belonging to the Lord Mayor of Bristol has been stolen.
The council said "thieves took a number of items" including the jewellery after a break-in at council premises near Brunel Lock during the morning.
Police said the suspects had forced their way into the building on Smeaton Road near the Cumberland Basin at about 05:30 GMT.
Avon and Somerset Police are asking anyone with information to contact them.
Bristol's current Lord Mayor is Liberal Democrat councillor Jos Clark.
There have been mayors in Bristol since 1216 and a Lord Mayor since 1899, following Queen Victoria's decision to grant Bristol this privilege.