Stephen Alderton shot dead father Gary Dunmore and his son Joshua (Picture: Cambridge Police)

A man killed his daughter’s ex-partner and her ex-partner’s father with a shotgun over a family court case they were all involved in.

Stephen Alderton, 67, shot dead the father, Gary Dunmore, and his son, Joshua Dunmore over a case involving his own grandson, a court has heard.

The father and son were found dead in homes six miles apart from each other in Cambridgeshire in March.

He was arrested hours after the attack by armed officers and told police ‘sometimes you have to do what you have to do even if it’s wrong in the eyes of the law’, said prosecutor Stephen Gair.

Gary Dunmore was found dead of a gunshot wound alongside his son (Picture: PA)

Alderton, who wore a crucifix around his neck as he appeared in a secure dock at Cambridge Crown Court, had written ‘I’ve a shortlist of people I intend to murder’ in a text message last year.

The defendant, who didn’t have a fixed address, pleaded guilty to the murders of 32-year-old Joshua Dunmore and 57-year-old Gary Dunmore at a hearing earlier this year on March 29.

His sentencing was due to take place today but it has been adjourned until Monday.

Mr Gair said Alderton committed the murders two days after a family court case took place.

Stephen Alderton, 67, pleaded guilty to their murders during a brief appearance before Cambridge Crown Court on Wednesday (Picture: PA)

Joshua Dunmore was found dead at his home in Bluntisham and his father at his home in Sutton – villages that lie six miles apart from each other in Cambridgeshire.

Mr Gair said: ‘We say it’s clear that the events were triggered by an ongoing family court case between this defendant’s daughter Samantha Stephen, nee Alderton, and her former partner Joshua Dunmore.

‘This concerned a request to move their seven-year-old child from the jurisdiction of the court by emigrating to the USA.’

He said Mrs Stephen and Mr Dunmore’s relationship ended shortly after their son was born.

Joshua Dunmore was found dead at his home in a village six miles away from his father (Picture: PA)

Then in 2020, Mrs Stephen married her current partner, Paul Stephen.

Mr Gair added that Mr Stephen, who is a US national, served with the US Air Force.

‘He was due to be redeployed back to the USA,’ Mr Gair said.

He continued, saying they ‘sought permission of the family court and Joshua opposed the application’.

‘There was a hearing on March 27 2023 and it would appear (the child) wouldn’t be removed from the jurisdiction,’ Mr Gair said.

Get in touch with our news team by emailing us at [email protected].

For more stories like this, check our news page.

Stephen Alderton sent a text saying he had a ‘shortlist of people’ he intended to murder, a court said.