Conservative general election candidate Sir Julian Brazier has laid into left-wing activists who barracked him at a political debate – accusing them of being “grounded in a sick mindset".

Two weeks ago Sir Julian, who is bidding for an eighth election victory in Canterbury and Whitstable on Thursday, faced sustained heckling at the Canterbury Christ Church University hustings.

He believes it came from a section of the audience which had turned up deliberately to barrack opponents.

“The problem at the event – and elsewhere – was not with biased chairmanship,” Sir Julian said.

“What has happened is that some on the Left have abandoned the principle that debate involves the exchange and testing of ideas and instead are resorting to simply trying to howl down the voices of anyone they disagree with.

“This unhealthy climate is grounded in a sick mind-set in which anyone with a different political view is wicked. So, in their world view, opposition to uncontrolled immigration makes someone a racist.

“Seeking to control runaway public spending and borrowing stems, they believe, from wanting to destroy public services.”

The Christ Church hustings saw the Conservative deputy chairman Neil Baker ejected after he twice loudly interrupted Labour’s candidate Rosie Duffield during her opening statement.

Although Sir Julian was also jeered and booed while he spoke, no one else was asked to leave the Old Sessions House lecture theatre in Longport.

He added that Ms Duffield had also spoken out against aggressive barracking.

Ms Duffield said: “Sir Julian is always really polite with me, but he really does need to bring more of his supporters along to things like the hustings at Christ Church.

“There is a lot of heckling at times. But Sir Julian is having to defend a record that many people think is indefensible.”

A YouGov poll has today put Ms Duffield slightly ahead of Sir Julian. The Canterbury and Whitstable seat has historically always been Conservative.

Lib Dem James Flanagan and Henry Stanton of the Green Party are also standing.