Police patrols have been stepped up at a converted shop in Cumbernauld town centre which has hit national headlines.
The Better Together campaign office in Forth Walk has not yet opened to the public.
Yet that did not stop a man claiming to be from the Scottish National Liberation Army from striding in on Wednesday, July 3.
The man calmly issued an ultimatum, telling two shocked young volunteers that that they would be bombed out if they did not vacate the premises within 24 hours.
He then left the campaign headquarters and disappeared into the mall.
The horrified members of staff then called the police.
Officers have revealed that they have been scanning CCTV footage to identify the man and that the investigation is continuing.
The incident has been widely viewed nationally as a new low in the independence campaign which has drawn accusations of dirty fighting on both sides.
MP Gregg McClymont who is heavily involved in the Better Together campaign said:“I was shocked to hear about this incident. It is clearly a serious matter and I am glad the police are dealing with it.
“My primary concern is for the young people who were in the office working for Better Together at the time and their well-being.
“There is no place for this kind of behaviour and intimidation should not be part of the debate on the best future for Scotland,’’ he added.
Meanwhile Scottish Nationalist Jamie Hepburn also expressed dismay at the incident.
He said: “Clearly this is a very serious matter.
“At this stage we do not know who this individual is but obviously I hope that he is apprehended as soon as possible. The issues we are debating are incredibly important and we are all responsible for creating and maintaining an atmosphere of mutual respect.
Volunteers are hoping to open the office in the near future and staff it round the clock to create a drop-in point for voters who want more clarification on key issues relating to the independence debate.
The referendum will take place ten weeks tomorrow (Thursday).
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