A man was jailed for life today for two murders and a string of "senseless" assaults.
Turkish Ali Koc, 30, pounced on his victims during a "wanton" crime spree of "violence for violence's sake", leaving them battered and bruised in parks and woodland close to his home.
One of two elderly men who died from his catastrophic injuries had been out on a routine morning walk which "cost him his life", prosecutors said.
Sentencing Koc at Woolwich Crown Court, south-east London, Mr Justice Calvert-Smith told him the unprovoked attacks illustrated the "diverse nature of London's population and the best and worst of its citizens".
Koc, of Hornsey in north London, was convicted by a jury of two murders and five counts of grievous bodily harm after a month-long trial.
The defendant, who lived on benefits and handouts from his parents, showed no emotion as he was told he would serve a minimum of 35 years, less the time he has already spent in custody.
Sentencing Koc, who has 18 previous convictions, the judge said the he had a "fondness for fighting" and became enraged after his welfare payments were stopped for an unknown reason shortly before his crime spree.
"I am certain that this (tendency towards violence) was increased by not being able to spend as much money as you had done in the past, even though your mother would help you out," Mr Justice Calvert-Smith said.
Describing Koc has a man who spent his days watching violent films, listening to music and wandering the streets, he added: "The attacks were vicious, random and with no motivation other than, in the words of one of the victims, 'the infliction of violence for violence's sake'.
"All illustrate the diverse nature of London's population and the best and worst of its citizens."
During a four-week period in January last year, Koc targeted lone men, selecting dog walkers, joggers or people who were simply out walking.
His victims, aged between 29 and 84, were "violently and indeed senselessly" subjected to either head-butting, punching, kicking or battery with lumps of wood, prosecutor Brian Altman QC told jurors at his trial.
Victor Parsons, 67, died on February 22 last year, while Koc's oldest victim. Keith Needell, was pronounced dead on July 16 the same year - nearly six months after he was set upon.
The five other men were not gravely injured but "that was not for want of trying", Mr Altman said.
"These were quite simply wanton attacks - violence for violence's sake - committed, say the prosecution, by the same man on a crime spree in the same geographical location of north London," he said.
"As a result, as you know, two men died of their injuries and others were left beaten and bruised by their ordeal."
Detectives have not ruled out the possibility that Koc may have pounced on others.
Each time he dealt the blows at a location within a 2.5km radius of his own address, in a part of the capital with which he was very familiar.
The attacks happened in broad daylight, usually before mid-morning or around lunch time.
Detective Chief Inspector Tim Duffield from the Metropolitan Police, described the spree as "brutal and sadistic".
"There can be no doubt that Koc is a highly dangerous and predatory individual who derived some warped sense of gratification from carrying out these abhorrent attacks," he said.
Paying tribute to Mr Parsons, his sister Rosemary said: "He was a good brother who stood by me when I needed him. He will be sadly missed."
Mary Needell, Mr Needell's wife, said: "Keith is greatly missed by all his family, friends and those whose lives he touched and enriched.
"Such a kind and gentle man should never have suffered in such a brutal and senseless manner."
In a victim impact statement read to the court ahead of sentencing, the son of retired quantity surveyor Mr Needell reduced one juror to tears as he spoke of his anguish and anger.
"I see an individual in the dock not adding to society, for taking money, support and other people's lives and happiness with a disdain for others," John Needell said.
"His selfish nature is such a complete opposite to my father that I wonder how he could ever be part of the same species as the rest of humanity.
"Frankly I pity him for what is obviously such a bleak and pointless existence.
"He is a weak individual that can offer nothing positive to anyone, even himself."
Members of Koc's family wept as the defendant, who lived with his parents, was led from the dock.
It came after the judge said relatives believed an addiction to cannabis set him on a path which led to his "brutal campaign of violence" and they offered no personal mitigation on his behalf.
Instead, the court was told Koc was a man of "bad character" who fostered anger towards the Department for Work and Pensions (DWP).
When his benefits stopped, he phoned the DWP repeatedly, sometimes hurling racist abuse at the call operator.
On one occasion, he even dialled 999 to complain about the service he was getting.
His previous convictions involved five counts of burglary or attempted burglary; three for assault, one for possession of a knife and a "large number" for possession of cannabis, the court was told.
He was jailed on five previous occasions.