The alleged killer of teenage motorcyclist Harry Dunn is “wanted internationally” after an Interpol Red Notice was issued for her arrest, a family spokesman has said.

Anne Sacoolas, 42, was charged with causing death by dangerous driving in December, but an extradition request submitted by the Home Office was rejected by US secretary of state Mike Pompeo in January.

In an email to the 19-year-old’s parents from Northamptonshire Police, seen by the PA news agency, the force said “the wanted circulations should be enacted” should Sacoolas leave the US.

According to Interpol’s website, a Red Notice is a request to law enforcement worldwide to locate and provisionally arrest a person pending extradition, surrender or similar legal action.

The Red Notice is not an international arrest warrant, but is issued for fugitives wanted for prosecution or sentencing.

The process is normally used so member countries can look out for the suspect, which usually assists with extradition proceedings.

Mr Dunn was killed when his motorbike crashed into a car outside a US military base in Northamptonshire in August last year.

Sacoolas, the wife of a US intelligence official based at RAF Croughton, claimed diplomatic immunity following the crash and was able to return to her home country, sparking an international controversy.

On April 30, a spokeswoman for the US State Department reiterated its position that at the time of the accident, and for the duration of her time in the UK, the driver had immunity from criminal jurisdiction.

The teenager’s mother said the news had been passed to the parents through their spokesman, Radd Seiger.

Charlotte Charles told PA: “It’s been a terrible time for us. We are utterly bereft and heartbroken and miss our Harry every minute of every single day.

“This is important news that Radd has just passed on to us and we are in pieces.

“I just want to urge Mrs Sacoolas to come back to the UK and do the right thing. Face justice and maybe then our two families can come together after the tragedy and build a bridge.”

Mr Seiger said: “Northamptonshire Police have confirmed to me that an Interpol Red Notice has now been circulated worldwide in respect of Anne Sacoolas.

“It renders her a fugitive on the run and it means that she would be arrested and returned to the UK the minute she attempts to set foot out of the USA.

“Red Notices would not be served on valid diplomats. I would urge the authorities in London and Washington and Mrs Sacoolas’s legal team to come together now to return her to the UK to face the English justice system where she will get a fair trial.

“I am sure that both families have suffered for far too long and it is time for her to do the right thing and come back.”

Later on Monday, Mr Seiger tweeted: “For those slightly confused, I can confirm that Interpol have circulated a Red Notice in respect of Anne Sacoolas.

“Police forces around the world are requested to locate her and provisionally arrest her with a view to her extradition to the UK.”