A British teenager who was killed in a car crash outside an American spy base in the UK was hit by a US diplomat's wife who claimed diplomatic immunity and has now left the country, it is claimed.

Harry Dunn, 19, was killed on August 27 near RAF Croughton in Northamptonshire.

The RAF base is one of the most important bases run by America in Europe.

Harry Dunn, 19, was killed on August 27 in a car crash near RAF Croughton in Northamptonshire

It was reported in initial findings by police were that Harry had been driving on the correct side of the road when a woman in a car pulled off of the airbase on to the wrong side of the carriageway.

The car hit Harry head-on and he died soon after in hospital after suffering multiple injuries.

Sky News has reported that the suspect involved is the wife of a US diplomat who quickly claimed diplomatic immunity following the incident.

It was reported in initial findings by police were that Harry had been driving on the correct side of the road when a woman in a car pulled off of the airbase

She had reportedly pulled on to the wrong side of the carriageway as she left the junction

The car hit Harry head-on and he died soon after in hospital after suffering multiple injuries

Harry's mother, Charlotte Charles, received a letter of condolence from US Ambassador to the UK Woody Johnson

Top diplomatic officials are immune from prosecution under diplomatic immunity, as are their deputies and families.

Northamptonshire Police had attempted to apply a waiver that would allow them to continue to investigate and conduct interviews.

But this application was declined.

The US Embassy has since confirmed that the woman has left the country.

Foreign Secretary Dominic Raab became aware of the incident and told Sky News: 'I wish to offer my condolences to the family affected by this tragic incident.

'I have called the US Ambassador to express the UK's disappointment with their decision and to urge the Embassy to re-consider it.'

Harry's parents, Tim Dunn and Charlotte Charles, have received a letter of condolence from US Ambassador to the UK Woody Johnson.

In it he said that 'it is with profound sadness' that he offered his condolences to the family but Mr Johnson made no reference to responsibility.

The US Embassy in London and Northamptonshire Police has been contacted for comment.