The father of Harry Dunn has confronted the foreign secretary in his constituency, where he is encouraging people to vote Dominic Raab out.

Raab was heckled during his final address at a hustings in East Molesey, Surrey, on Monday evening, with one woman standing up to ask him about Dunn, whose family and friends were kept outside for the duration of the event due to purported concerns about overcrowding.

Raab was later confronted by Tim Dunn, Harry’s father, and friends of the late 19-year-old as he left the building and was ushered into his official car. Police officers and security staff were stopping people from blocking the exit, while the crowd booed Raab and shouted “coward” as he drove away.

“We were receiving live tweets from Harry Dunn’s family members, and his father, who travelled down with family members, to go into the hustings and speak to Dominic Raab,” said Rebecca Little, a local resident who stood up to address the foreign secretary.

“I was shut down by the shouting when I stood up but I could see other people in the audience saying ‘come on, let them in’. There were several security detail preventing the family from coming in but they have a right to enter the hustings.

“When Raab’s heavies are preventing them coming in, I believe the people in there had a right to know.”

Tim Dunn and Charlotte Charles, whose son Harry died on 27 August when his motorbike was involved in a head-on crash with a car outside RAF Croughton in Northamptonshire, had vowed to put pressure on Raab in the Esher and Walton seat.

The 19-year-old’s death sparked an international row when the woman suspected of driving the car, Anne Sacoolas, claimed diplomatic immunity and was allowed to return to the US.

Dunn and Charles have previously criticised the Tory candidate and the family’s lawyers have sought legal action against the Foreign and Commonwealth Office (FCO).

Ahead of the constituency visit, they said they planned to confront the foreign secretary on why he “steadfastly refuses to publicly call for Mrs Sacoolas to be returned to the UK”.

They said: “We are not political people. Whatever political thoughts we hold we generally keep to ourselves.

“But the enormity and shocking nature of what has happened to us have left us feeling compelled to come to Esher and Walton this evening in the midst of the current election campaign.

“We feel that his handling of our situation has been so outrageously dishonourable and disrespectful that we have a duty to respectfully bring these matters to the direct attention of that local community that have until now voted him into this position.”

Dunn’s family have urged locals to vote for Monica Harding, a Liberal Democrat hopeful standing against Raab.

A claim by the family, which alleged that the granting of diplomatic immunity to Sacoolas was “wrong in law”, was met with strong resistance from the FCO – which told them it would oppose and seek costs for any legal action.

“Although we do not take part in any form of party politics, we invite people, irrespective of how they normally vote, to consider very carefully how they cast their vote on 12 December,” Dunn and Charles said.

“This is not about left or right. It’s about trust and right versus wrong.

“People will need to form their own judgments of course but given our experience of Mr Raab’s behaviour, we strongly believe that he is not worthy of holding public office.”

The Dunn family urged locals to consider what they claimed was “the disgraceful manner” in which Raab had behaved.