A self-styled wrestling expert has been jailed for life for choking a disabled man to death.
Fitness instructor Khorram Azim was found guilty of murdering Kevin Beckingham, a partially blind and epileptic fitness client in February.
Azim, 34, from Sidcup, Kent, killed him after learning the "choke hold" from a wrestling video, the Old Bailey heard.
Azim denied murder, but admitted trying to cover up the crime. He must serve at least 17 years.
Azim was prone to fly into a rage at the merest slight, the jury was told.
Judge Gerald Gordon told Azim: "Your motive is to me a mystery and will remain so."
After the killing, the court heard Azim tried to cover up the murder by stabbing Mr Beckingham five times in the neck.
He then orchestrated a campaign involving his girlfriend and a friend to throw police off the scent, and pin the blame on another man.
Jurors also heard Azim made a "series of bizarre remarks" to officers claiming the murder was linked to terrorism.
It was weeks before Mr Beckingham's body was found at this home in Plumstead, south London.
After the verdict, Mr Beckingham's mother Brenda told the judge that they would never get over her son's death.
"He was killed for no reason," she said. "There are still many unanswered questions."