The killers of a father-of-two must serve a minimum of 15 years in prison, a judge has said.
Colin Horner, 35, was shot dead by a lone gunman in front of his three-year-old son outside a supermarket in Bangor, County Down, in May 2017.
Last week, four men pleaded guilty to murder. They were sentenced on Tuesday.
Police have linked the killing to an ongoing south east Antrim UDA feud in which Geordie Gilmore was also killed in March 2017 in Carrickfergus.
Two of the men who were in court on Tuesday must serve at least 16 years, one was sentenced to 15 years and six months and another must serve 15 years.
Alan James Wilson, 30, of North Green, Newtownards, and 31-year-old Bangor man Ryan Graham Smyth, of Windsor Gardens, were given the highest prison terms.
Joseph Blair, 35, of Shackleton Walk, Newtownards, must serve 15-and-a-half years while Robert Ralph, 47, of Donaghadee Road, Newtownards must serve 15 years.
'Cold and brutal murder'
The men had been handed automatic life sentences, but on Tuesday they found out the minimum time they must serve before being considered for parole.
At an earlier hearing, Mr Horner's killing was described by a prosecution barrister as a "professional or contract killing".
A man and a woman also admitted withholding information about the murder.
In court on Tuesday, Adrian Gordon Price, 48, of Bristol Park, Newtownards, was sentenced to 12 months, suspended for two years and Terrie Aicken, 24, of Green Road, Conlig, was sentenced to three months, suspended for 12 months.
Speaking after the sentencing, PSNI Det Ch Insp Peter McKenna said it was "a cold and brutal murder" carried out in front of the victim's young son.
"It is inconceivable that Colin's son, who was just a toddler at the time, had to witness his father's murder and this is a memory that he will carry with him for the rest of his life," he said.
"Colin was also the father of a little girl who was just two years old when her daddy was taken in such a callous manner.
"This was a premeditated murder, which I believe was linked to an ongoing south east Antrim UDA feud.
"The victim was followed throughout the day by a second vehicle, a black Ford Focus, in the lead up to his death and this enabled the gunman to pull up in the [Ford] Mondeo at the supermarket and end Colin's life in a matter of seconds.
"The thugs responsible for this murder are hypocrites who think they have a right to act as judge, jury and executioner."
Mr Horner's partner, Natasha, welcomed the sentences.
"Knowing that the people responsible for Colin's death are now behind bars is a relief for me, my daughter but more so my son, as he now knows the 'bad guys' are in jail and can't hurt him any more," she said.
After the sentencing, Mr Horner's mother, Lesley, said: "I know there are families out there who haven't had justice... I'm not saying we are lucky, luck doesn't come in to it. The pain this has caused me and my family, it has just been excruciating."
She said her son would live on through his two children "and through me as I will keep his memory alive forever".
She thanked the police for their work in bringing her son's killers to justice.
"Also, to the police family liaison officers for showing love and compassion at the worst time of our lives, we thank you," she said.