MINDLESS vandals struck at the Caernarfon Plaid Cymru office daubing the word "scum" on the door.

Police are investigating the incident, thought to have happened on Tuesday night.

Staff discovered the problem at the Castle Street office as they turned up for work at 8am, on Wednesday morning.

Police attended the scene, to check on the staff, and to investigate the incident given the threats directed at MPs in recent months.

Arfon MP Hywel Williams said: "In all likelihood this is an act of mindless vandalism.

"I’m reassured that the police are treating the matter with the seriousness it deserves, and I would like to thank officers for their quick response.

"My staff are entitled to work free from fear and intimidation just like everybody else. They should not be made to feel threatened at their place of work."

‘We are aware of the criminal damage.

A police statement said: "Officers are currently in attendance (Wednesday) and we are appealing to anyone who may have information relating to the incident to contact police on 101 quoting reference X048042."