A book of condolences for former Preston City Council leader Peter Rankin has been vandalised.
Sections of the book, which was left in the city's town hall, have been ripped and have had to be removed.
Mr Rankin died earlier this month at the age of 67 after developing a brain tumour.
The book was damaged on Tuesday between 13:30 and 15:00 BST, said the council. Police have been notified and CCTV footage is being reviewed.
The council said the book will now be only available by request from the town hall's reception desk.
Anyone who left an entry in the book has been asked to come back and write a second one or submit one online.
The Labour politician stood down as council leader in May, a post he previously held between 1997 and 2000, before serving again from 2011.
Council leader Matthew Brown said Mr Rankin had been a "great champion of Preston".
A spokeswoman for Lancashire Police said: "We are investigating a report of criminal damage at Preston Town Hall."