UKIP campaigners in Salisbury were attacked as they set up a street stall.
A man physically assaulted them and subjected them to verbal abuse as they were preparing their information stand outside the Library in the city.
Campaign manager, Pat Conlon, said: “It was highly traumatic but the police were very helpful and are investigating.”
Undeterred, the group plan to return to the pitch two further occasions before the elections.
UKIP was barred from taking part in a hustings event at a school in the city last week.
Party Leader, Gerard Batten, said: “Sadly this is not the first time it has happened to our party activists going about their lawful business and doubtless it will not be the last.
“I am glad the police have taken this seriously and have the camera footage to show what has happened.
“Lastly, it shows what we face to get the truth out into the real world but we are not being deterred.”