A martial arts thug who murdered a vulnerable granddad in a wheelchair was today branded a “vile bully” by the victim’s family.

Daniel Sharples, 38, roundhouse-kicked dad-of-two Michael Mairs, 53, tipped him out of his chair, then booted him in the head as he lay unconscious on the ground in an unprovoked attack.

The drink and drug fuelled killer fled after the “vicious” attack and amputee Mr Mairs died from his injuries three weeks later, Liverpool Echo reports.

Sickening footage of the attack was released by Cheshire Police with the permission of Mr Mairs’ family.

Sharples when caught told police his victim previously tried to sell his son “smack” and spice saying “I’m glad I did it and I’ll do it again”.

But the killer’s two sons both told police they had never taken the drugs or been given them by Mr Mairs, who they had never even met.

He admitted manslaughter but denied murder on the basis he was too “out of control” to form the intent to either seriously harm or kill Mr Mairs.

However, a jury unanimously found Sharples guilty of the murder, which took place under a railway bridge in Warrington, just after midday on October 6 last year.

Following the verdict, Mr Mairs’ son and daughter said: “What Sharples did on the afternoon of October 6 last year will live with us forever.

“That day, Sharples set out to kill and our dad was unfortunately caught in the crossfire.

“We will never forget the funny, bubbly, caring man our dad once was.

“We, as a family, would like to thank all the witnesses who came forward and those who tried to help our dad that day.

“We are more than grateful.” They said.