Graffiti vandals causing hundreds of thousands of pounds worth of damage every year in Leicester are being targeted in a new crackdown.
A joint campaign by police and the city council, called Graffiti is a Crime, is urging residents to report incidents.
The authority spent £250,000 last year on graffiti removal, a city council spokesman said.
A £500 reward is now being offered for information leading to the successful prosecution of vandals.
There will be clean-up sessions in the worst affected areas of the city as part of the campaign and DIY graffiti clean-up kits will be given out as a trial to residents and businesses.
Councillor Sarah Russell, Leicester City Council cabinet member for environment and sustainability, said: "We want people to report graffiti in their areas so that we can take steps to get it removed before it escalates.
"We want to send out a clear message that graffiti is a crime and we are working hard to find out who's behind it and get to the root of the problem.
"In many cases vandals use their own 'tags' - stylised signatures - and someone must know who created them. We hope that offering a reward for information will help put a stop to it."
Ch Insp Martin Halse, from Leicestershire Constabulary, said: "Graffiti amounts to criminal damage therefore anyone suspected of committing graffiti runs the risk of being arrested, charged and put before a court."