The tags, created with marker pens and spray paint, have been appearing in locations in Maidstone town centre and on the outskirts since October 2005.

A boy aged 15 from Staplehurst, another from Maidstone and a 14-year-old boy from Linton were arrested and formally cautioned for criminal damage.

Kent Police said such anti-social behaviour was not acceptable.

Damaging image

The graffiti was discovered in Fairmeadow, Wat Tyler Way, Armstrong Road, Loose Road and Linton Road.

"Actions like this are taken seriously by Kent Police," said a spokesman.

"Some might see graffiti as being relatively harmless but it can be damaging to the image of the local area.

"It can also heighten people's perception of crime, causing fear and anxiety for local residents."