Dale Cregan has been sentenced to life imprisonment for the murder of two police officers – one of whom was planning to enter into a civil partnership.

The 30-year-old was the main suspect in the murders of Greater Manchester Police officers Nicola Hughes, 23, and Fiona Bone, 32, who died in September last year.

Cregan admitted the charges on the fourth day of his trial at Preston Crown Court in February 2013.

Later on in proceedings he also pleaded guilty to killing father and son David and Mark Short.

Cregan has been cleared of a final charge of attempted murder at the conclusion of a 12-week trial involving nine other men.

Fiona Bone, who had been planning to enter into a civil partnership with her girlfriend Clare Curran, when she lost her life, was laid to rest in Moray in north-east Scotland, last November.

Following the trial, PC Bone’s father Paul said the killings were “unreal – the level of callousness is beyond my comprehension”.

Nazir Afzal, chief crown prosecutor for the north-west of England, said the killings were “nothing short of executions”.

Greater Manchester Police Commissioner Tony Lloyd said the case cast a “long, dark shadow” across the city.

Commenting on the murder of PC Bone and PC Hughes, Greater Manchester Chief Constable Sir Peter Fahy said: “The British public prize the fact that their police force is routinely unarmed and saw this attack as an attack on all of us.”