After three killers pleaded guilty in the death of Trevor Lomond, a Calgary judge released video of the initial attack and kidnapping.

Originally charged with first-degree murder, Mahad Dirir, 32, Abdulrizak Jeyte, 31, and Ahmed Farah, 33, pleaded guilty to manslaughter Monday in the 2016 death of the 33-year-old Calgarian.

Trevor Jordan Lomond died in hospital on Sept. 21, 2016. (Facebook)

Last week, prosecutors stayed the murder charge against 31-year-old Mohamed Abdullahi Hassan, 31.

Crown prosecutors Ken McCaffrey and Kane Richards proposed six to eight years in prison while defence lawyers argued their clients should receive a five-year sentence. Provincial court Judge Frank Maloney will sentence the killers next week.

According to Dirir's lawyer, Allan Fay, the victim and the killers were involved in a cheque cashing scheme. Fay said Lomond was suspected of withholding money from the trio.

On Sept. 13, 2016, after following Lomond, he was confronted outside a friend's home.

He tried running away but Jeyte and Dirir attacked him, demanding money and yelled "grab him, get him in the car."

After three killers pleaded guilty in the death of Trevor Lomond, a Calgary judge released video of the initial attack and kidnapping. Read more: www.cbc.ca/1.4552423 1:04

They can be seen putting Lomond in a car, driven by Farah, and taking off.

A neighbour's surveillance camera caught the initial attack and kidnapping on video, which Maloney released to the media on Monday.

​Lomond can be seen being kicked in the head before being forced into a car.​

Victim found in southwest basement

Dirir, Jeyte and Farah then transported the victim to a home in the southwest community of Rosscarrock around 6:30 p.m.

Just 40 minutes after the kidnapping, Farah used Lomond's bankcard.

Around 11 p.m. that night, police responded to a 911 call reporting an unconscious man.

First responders found Lomond in the basement, a pool of blood around his head with injuries to his mouth and eyes. He was unresponsive and his breathing was laboured.

Despite emergency surgery to relieve brain bleeding and swelling, Lomond died a week later from more than eight injuries to his head and neck.

Farah's fingerprints and Dirir's DNA were found at the scene. Jeyte confessed to a friend that he, Dirir and Farah had kidnapped Lomond, tied him up and "knocked him out" three times and on the third time, the victim "never came back."

'I smile but my heart sobs,' says victim's mother

In her victim impact statement, Sherry Duperre wrote about her son's final moments as he took his last breaths in hospital.

"With an overwhelming sense of hopelessness, I watched as my son was fading with each breath," said Duperre.

"From the moment his last breath was taken, I in turn breath but I feel like I'm dying. I smile but my heart sobs."

Lomond's father said after grieving several family members he knows both the the "joy of life" and "the sorrow of death" but his son's killing was the most painful by far.

"I, like so many others can bear witness to the statement that we have all heard so many times: 'There is no loss like the loss of a child.'"