A MAN who killed his mother’s lover is back behind bars for slamming his own ex’s head against a door.

Sean Mahan, 26, was jailed for attacking Stewart McKellar, 33, at the family home in Luss Road on August 23, 2014.

He was jailed for just four-and-a-half years and let out on licence in October 2018, heard Dumbarton Sheriff Court yesterday.

There was outrage at Mahan’s original short sentence and many comments on social media about how Mr McKellar would be missed.

But Mahan again flew into a rage when, on April 1 this year, at a property in Main Street, Renton, he repeatedly kicked and struck the front door, demanded entry, shouted and swore, smashed a window of the door and placed his ex partner and two other women in a state of fear and alarm.

He also broke into the property and assaulted his ex, seizing her by the hair and striking her head against a door. He pleaded guilty last month.

Mahan’s defence solicitor told the court that her client had been in a full-time job after he was released on parole, in the “very gruelling” concrete trade.

She said: “He fully accepts there will be a custodial sentence.”

Read more: Balloch man jailed for four and a half years for battering Stewart McKellar to death

The Crown confirmed Mahan’s ex did not request a non-harassment order.

Sheriff Maxwell Hendry told Mahan, a prisoner of Low Moss: “You’re a 26-year-old man with a short but worrying record. The report makes clear you have issues you must address.”

Mahan was sentenced to 24 months in jail, backdated to April 25. He will also be subject to 12 months supervised release after the prison term.

In August 2014, Mr McKellar had been out with friends at the Lomond Park Hotel, and he was described as “being in good spirits” and “enjoying the company”.

There he met Mahan’s mother, who took Mr McKellar home while her husband was working offshore.

Mahan discovered the two in bed and subjected Mr McKellar to a “prolonged assault”, lasting up to 20 minutes. He then slapped his mum, calling her a “slut”.

Then aged 21, he called a friend, stating: “This guy was sleeping with my mum and I think I have killed him.”

Mahan was later found by police hiding in the kitchen cupboard of a friend’s home.

He told cops: “I only punched him. What would you have done? I came home to find my mum in bed with someone else.”