A man at the heart of last year's Croydon riots had his sentence of four years detention nearly doubled today.
Adam Khan Ahmadzai, 20, of Feltham, west London, was given 48 months in a young offender institution when he appeared at Inner London Crown Court in January.
Attorney General Dominic Grieve referred the case to the Court of Appeal on the basis that the total sentence imposed for offences of violent disorder, robbery, burglary and criminal damage on the evening of August 8, 2011 was unduly lenient.
Today, the Lord Chief Justice Lord Judge, sitting with Mr Justice Openshaw and Mr Justice Irwin, agreed and said it should be increased to seven years.
Lord Judge said: "These were offences of great seriousness."
The Attorney General, who presented the case to the court, said later: "Adam Khan Ahmadzai was at the very heart of the looting and rioting in Croydon last August.
"Consider the extraordinary list of crimes that he committed: he led an attack on a police line; robbed a bus driver who he had forced to halt; armed himself and ransacked a shop, forcing the petrified owners to flee, only to rob them moments later in a hijack of their van; repeatedly attacked and mugged a terrified man at a cash machine, acting as if pushing a gun into his neck; led a gang into a supermarket, looting and vandalising; and finally directed his group into a betting shop, destroying a fruit machine and looting the office behind the counter.
"For this catalogue of mayhem and carnage he received a four-year sentence. I'm very pleased that the Court of Appeal has today quashed that sentence and replaced it with one of seven years."
CPS London chief crown prosecutor Alison Saunders said: "We referred this case to the Attorney General as one that had attracted a sentence which was unduly lenient.
"I welcome the strong message that the Court of Appeal has now sent out as a result of this ruling.
"Adam Khan Ahmadzai was a ringleader during the riots in Croydon and his conviction for 10 offences committed that night shows the extent of his criminality.
"His offences were amongst the most serious which CPS London has prosecuted in relation to the summer riots and this increased sentence reflects that."
Ahmadzai buried his head in his hands as he sat in the dock of the court while Lord Judge recounted the ordeal of a convenience shop owner, who was beaten up in front of his wife and and saw his business ransacked.
When the couple tried to escape in their van, they were both pulled out of the vehicle and a knife was held to his stomach.
Lord Judge said the man had moved into Croydon to make a fresh start and build a new life in the community, and that was beginning to happen before the riots.
But what had happened had affected him more than he ever thought possible, so he had pulled out of the business and was now unemployed and in great financial difficulty.
This offence on its own was of the "greatest possible seriousness", he added.
Ahmadzai, who used a brick, a wooden and a metal pole, a hammer and a waste bin as weapons, had pleaded guilty in the context of his identification on CCTV footage and from blood found on the cash machine.
The judges went on to dismiss an appeal against a five-and-a- half-year prison sentence imposed on 23-year-old Zac Challinor for offences of arson, burglary and violent disorder in the riots in Manchester on August 9 last year.
Challinor, of Wythensawe, Manchester, was part of mob violence which left 49 police officers injured and resulted in a BBC Radio Manchester van being torched in Salford Shopping City, causing £60,000 damage.
Confronted with CCTV footage, he admitted his guilt and expressed disgust at what he had done.
Rejecting the appeal, Mr Justice Openshaw said the sentence handed down at Manchester Crown Court in January was severe, as intended to be, but not manifestly excessive.