Actor Jamie Waylett, who played Hogwarts bully Vincent Crabbe in six of the Harry Potter films, was jailed for two years for being part of a mob during last summer's riots in London.
Waylett, 22, was found guilty of violent disorder by a jury at London's Wood Green Crown Court, the Press Association reported.
Waylett, who already had a previous conviction for cannabis possession, was with a gang of at least four people who went into the Chalk Farm area of north London last August on the third day of violence in the capital.
He was captured on CCTV at various points during the evening, often with a hood over his head.
The footage shows him accepting a bottle of champagne from a rioter who had just looted the supermarket he was standing outside.
Judge Simon Carr sentenced the actor to two years for violent disorder and 12 months for handling stolen goods, to run concurrently.
Jailing him, the judge said: "Anyone watching the footage in this case can only imagine the mayhem that took place on the streets.
"You chose to go out on to the streets on what was the third day of the violence. You were pictured on a number of occasions with a bottle full of petrol with a rag as a wick.
"I accept ... that you did not throw or have any intention of throwing it, but merely being in possession of it would have been terrifying to anyone who saw you."
Judge Carr told Waylett he would be eligible for release after a year in jail.
The star, who had a shaved head and a goatee beard, wore a white shirt with an open collar and a dark suit to hear the sentencing.