A man who used a Rambo-style knife with a 10-inch blade to stab a stranger to death following a row over a cigarette has been jailed.
Jahmel Riley, 25, was convicted of murdering Dennis Anderson, 39, in the early hours of 10 February.
Riley attacked Mr Anderson at an off-licence on Lordship Lane, East Dulwich, after he had been refused a cigarette.
He was sentenced to a minimum of 23-and-a-half years at the Old Bailey.
Judge Nicholas Hilliard said the killing showed the dangers of carrying knives.
“What might otherwise have been just a verbal disagreement becomes a murder case because the defendant was carrying that terrible weapon,” he said.
Jurors heard how Riley had been “hustling” customers at the Pay Less shop for a cigarette, when Mr Anderson responded: “Why are you asking for cigarettes? Why don’t you get a job like the rest of us?”
Prosecutor Duncan Atkinson QC said a confrontation then began, where the defendant produced and unsheathed the large Rambo-style knife he was carrying.
Mr Anderson tried to disarm Riley and, as they both fell to the ground outside the store, CCTV showed Riley making a stabbing motion towards Mr Anderson’s neck.
The double-edged knife used in the attack was abandoned at the scene.
Riley claimed Mr Anderson was the aggressor and the stabbing was accidental.
However, prosecutors argued Mr Anderson’s injuries “told a very different story”, showing a series of deliberate blows to the upper body.
Mr Anderson’s partner, Leeane Manzi, said: “On the night that he was so brutally attacked, Dennis showed the heroic qualities that we all knew him for by trying to protect other members of the public and stop the situation escalating.
“This did not surprise us when we found out, as looking out for others summed up Dennis’ character.”
She added the attack had left their “hearts shattered and our lives turned upside down”.