In an exclusive story yesterday, this newspaper reported that a leaflet with UKIP branding had been sent out telling potential 'state enemies' that 'we're watching you'.
The national branch UKIP have distanced themselves from the 'sinister and threatening' leaflet, which was delivered to homes in Sussex and at Westminster.
The flyer, which carries the purple UKIP branding, sets out why the party thinks MPs should vote against the Prime Minister's deal.
However a notice in block capitals at the bottom has caused outcry. It says: "We would classify anyone prepared to vote for this agreement as a national traitor, or state enemy - and we're watching you."
One Chichester resident who received the flyer hit out at the 'threatening' language.
They said: "I thought it was an outrageous thing to say. It was sinister and threatening.
"It saddens me that we have reached a point where anybody thinks this is acceptable."
Chichester MP Gillian Keegan told the BBC that being called a traitor is "very divisive".
She called for 'respect' for differing views on Brexit..
There have been calls for the matter to be reported to the police since a photo of the leaflet was shared on social media.
The flyer states that the UK’s law, security and trade would all be “destroyed” by Theresa May's deal.
Ukip came fifth in the Chichester constituency at the 2017 general election, winning 2.8 per cent of the vote.
A spokesman from UKIP head office said: "The material in question was not sanctioned by UKIP Head Office, and as such is not an official communication of the national United Kingdom Independence Party.
”UKIP is investigating the source of this material.”
Both the South East regional branch of UKIP and the West Sussex branch have been approached for comment.