For five weeks residents and businesses in Borough and Bankside have found ground-floor windows smashed with bricks in a mysterious series of early-morning incidents.
The first incident was recorded on Wednesday 23 January. The offences seem to be centred on the Union Street area, although windows have been smashed as far away as Sumner Buildings and Manciple Street.
A police spokesman wouldn't confirm how many reports they had received of broken windows.
"The offences have been very sporadic," said Sgt Steve Dutton of Cathedrals safer neighbourhoods team.
"Local police have been conducting high visibility and plain clothes patrols at various times.
"We ask that if anybody sees anything suspicious or the offence has just been committed to dial 999.
"Unfortunately one local resident watched the suspect smash several windows without contacting the police for fear of repercussions.
"Even if you don't want to give the information to the police direct, you can contact Crimestoppers anonymously on 0800 555 111.
"Cathedrals SNT encourage residents to make contact with their local safer neighbourhoods team if they have any concerns."
Members of Cathedrals SNT will be available to hear people's concerns and receive information at their office in Trundle Street on Friday 1 March between 5.30pm and 6.30pm.
For the latest local news and events direct to your inbox every Monday, you need our weekly email newsletter SE1 Direct.
7,000+ locals read it every week. Can you afford to miss out?
Read the latest issue before signing up