Published: 12:00, 02 May 2014 |
Updated: 10:31, 06 May 2014
The edited posters with rewritten messages attacking the party's policies on labour and its belief that Britain no longer has control over making its own laws appeared last Sunday.
One of the alterations reads "Have you tried hating foreigners… We think you'll like it" underneath a UKIP claim that 75% of laws in Britain are made in Brussels and the question "who really runs this country?".
Another replies to UKIP's suggestion EU laws are hitting British workers with "unlimited cheap labour" by saying instead UKIP is "keeping low paid jobs for British workers".
But today Kent Police today confirmed it was investigating.
UKIP county councillor for Folkestone, Frank McKenna, said he had contacted the police about the vandalism to the posters.
A Kent Police spokesman said: "Kent Police is investigating reports of criminal damage that occurred between April 20 and April 28 to billboards along Black Bull Road, Folkestone.
"No arrests have been made and inquiries are ongoing."
It is unclear from where the mysterious slogans have emerged.
UKIP is a long-term opponent to the UK's membership of the European Union and is against British involvement in the European Parliament in Brussels.
The posters are at the bottom of Blackbull Road, the junction between Canterbury Road and Dover Road and opposite The Cube in Tontine Street.
UKIP holds all three Folkestone seats at Kent County Council after elections last May.
Leader Nigel Farage told KentOnline earlier last month he would "more than likely" stand in Kent in the General Election next year.
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