The killers of PC Andrew Harper have had their sentences referred to the Court of Appeal after the attorney general considered them to be "unduly lenient".

Suella Braverman QC said attacks against emergency workers should be "punished with the greatest severity".

PC Harper, 28, suffered catastrophic injuries when he was dragged behind a getaway car in Berkshire last August.

Henry Long, Albert Bowers and Jessie Cole were convicted of manslaughter.

The driver, Long, 19, was jailed for 16 years while his passengers Bowers and Cole, both 18, were sentenced to 13 years each.

The three teenagers were all cleared of murder charges following a trial at the Old Bailey in London.

'Such heinous crimes'

The unduly lenient sentence (ULS) scheme allows victims of crime, their families, prosecutors and the public to ask law officers to review sentences for certain crimes that they believe are too low. It only requires one complaint for the attorney general's office to consider whether to refer the matter to the Court of Appeal.

The Attorney General Suella Braverman said PC Harper's killing was a "horrific crime which resulted in the death of a much-respected police officer while he was on-duty, protecting his community".

She said she had referred the sentences after "having personally considered the details of this shocking case".

"Offenders should be punished with the greatest severity for such heinous crimes," she added.

The referral comes after PC Harper's widow Lissie and his mother Deborah Adlam launched campaigns calling for tougher sentences for killers of emergency service workers.

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Speaking in the witness box was "one of the hardest things" she had done, Mrs Harper previously said.

"So at the end of it, to not get any real justice is heartbreaking," his widow told the BBC.

Reacting to the attorney general's decision, Mrs Adlam said: "My family and I know that the whole nation stands with us in outrage at the sentences handed down to my son's killers.

"We can only hope that a fairer outcome is reached by the Court of Appeal to deliver the justice that Andrew deserves."

The maximum sentence a judge can impose for manslaughter is life imprisonment but they must specify a minimum term to be served.

What is the Unduly Lenient Sentence (ULS) scheme?

• The scheme allows victims of crime, their families, prosecutors and the public to ask law officers to review sentences for certain crimes that they believe are unfair.
• The attorney general can only ask the Court of Appeal to review a sentence under the ULS scheme if they consider that sentence to be "unduly lenient". It means, for example, that a sentencing judge made a gross error or imposed a sentence outside the range of reasonable sentences available.
• The scheme only applies to sentences given in crown courts in England and Wales.
• The attorney general acts independently of government when deciding on unduly lenient sentences.

Source: Attorney general's office.

Mr Justice Edis, the sentencing judge in the case, told the Old Bailey each of the jail terms for PC Harper's killers had to reflect "the seriousness of this case".

A date for the hearing at the Court of Appeal has yet to be set.

PC Harper, from Wallingford, Oxfordshire, died after he responded to reports of a quad bike theft with a colleague hours after their shift had ended on 15 August 2019.

A trial at the Old Bailey heard as PC Harper attempted to apprehend one of the three defendants, his feet became entangled in a rope trailing behind a getaway car.

As the Seat Toledo sped off, the officer became "lassoed" to the back of the vehicle and was dragged for more than a mile along country lanes to his death.