On CCTV, the train steaming gang set out on a mission of menace

Strutting and intimidating, they took their name from their belief that they would never be caught.

As the gang today start their jail sentences totalling 23 years, the threat of violence they posed to commuters is clear.

The CCTV pictures were taken at the height of the gang's eight-month campaign, in which they robbed men, women and even a 15-year-old schoolgirl on the capital's trains and Tube network. They struck at a number of stations from Liverpool Street to Fairlop Waters, Walthamstow Central, Seven Sisters, Stoke Newington and Loughton.

Gang leader Melvyn Gay, 27, threatened to knife terrified victims if they did not hand over cash, jewellery, mobile phones and iPods.

Sentencing the gang members at Southwark crown court, Judge James Wadsworth said: "Every weapon on the streets, even if it is concealed or out of sight, used or unused, is a threat to public safety because in a moment of drunkenness or anger there can follow offences of the greatest seriousness.

"And when you went out stoked up on drugs and alcohol in possession of a knife it was a very nasty matter indeed."

Outside court Detective Constable Jon Pine, of British Transport Police, said that the gang robbed indiscriminately and instilled fear in their victims. "They targeted men, women and children and warned them of severe consequences if they resisted their demands," he said.

"They thought that they were a law unto themselves and had absolutely no conception of the trauma and fear experienced by those who had the misfortune of being picked on."

He added: "These people behaved as if they would never be caught.

"But what they failed to recognise is that they were so often captured on camera by CCTV systems on trains and at stations, which proved invaluable in helping us to track them down and bring them to justice.

"Passengers should be aware that robberies on the railway network in London are significantly down, and that CCTV is proving increasingly valuable in tracing offenders who think it is acceptable to inflict misery on law abiding people."

Gay, from Walthamstow, was jailed for nine years.

Douglas Lawrence, 20, from Tottenham was jailed for five years and Sheldon Williams of Clapton and Aaron Flemming of Hackney - both also 20 - each got four-and-a-half years.

They all admitted conspiracy to rob between April and November last year. Gay alone admitted nine robberies and Williams and Flemming each pleaded guilty to four charges of robbery.