One-eyed Dale Cregan is currently serving a life sentence for brutally killing four people, including two policewomen, in 2012 with guns and grenades.
Cregan’s killing spree started when he murdered amateur boxer Mark Short, 23, at a pub in Droylsden, Manchester, in April.
Three other people, believed to be related to the victim, were also wounded, suffering leg and back injuries.
Four months later Mark Short’s father David was killed in a gun attack in Clayton, Manchester. Mr Short had branded his son’s murderers ‘cowards’.
Nine minutes after the incident, police received reports that shots had been fired at a second property in Droylsden, where there was also a grenade blast. Nobody was injured in the incident.
Detectives said they wanted to speak to Cregan, who they had released in May after linking him to the first murder but did not have the evidence to charge him.
In September that year the killer used a fake 999 call to lure officers Fiona Bone and Nicola Hughes to a house.
When they arrived, Cregan shot them and threw an M75 grenade at them. Both officers were hit by at least eight bullets as Cregan fired 32 shots in 31 seconds.
He later handed himself in at a police station, admitting to killing the unarmed women.
The gangster admitted the attempted murder of three others in a high profile court case the following year.
During his four-month trial, which began in February 2013, Cregan was detained at Manchester Prison.
The trial was held at Preston Crown Court, where scaffolding was erected to accommodate armed officers.
Police snipers watched over the building from nearby offices and the daily convoy, carrying Cregan between Manchester and Preston, included two prison vans, police cars, motorcycle outriders and a helicopter.
In total 120 Greater Manchester Police officers were deployed daily and the total cost of the trial was estimated to be in excess of £5 million.
Cregan was convicted of all four murders and three attempted murders and was sentenced to life imprisonment with a whole life order on June 13, 2013.
He was told he would never see release after admitting to the killings which prompted public outcry and an outpouring of sympathy for the police.
His accomplice, Anthony Wilkinson, was jailed for a minimum of 35 years for his part in the gun and grenade murder of David Short.
In April 2015 he was temporarily moved to the high-security psychiatric unit Ashworth Hospital in Merseyside after going on hunger strike for a second time.
He was said to have started refusing food at the Category A jail HMP Manchester, formerly known as Strangeways, after being moved to solitary confinement.