A social worker responsible for two teenage members of a gang that robbed and terrorised commuters on the London Underground was dragged from court yesterday after a dramatic tirade about gang culture.

Liz Johnson appeared to have become overwhelmed by the spiralling gang violence among black teenagers in London. She clambered over two rows of desks at Middlesex Guildhall Crown Court and jumped into the witness box feet from Judge Henry Blacksell. She then leant over and screamed at him: “I’m a social worker. I’ve just lost my job.”

Ms Johnson was in court to see the sentencing of two of her clients who were part of the gang that rampaged through Tube carriages, robbing at least 36 passengers. Two members of the gang have already been convicted of the murder of the lawyer Tom ap Rhys Pryce.

Her outburst started with an apparent reference to the murder of Kodjo Yenga, 16, in West London, last week.

“That boy that was lying on the floor dying. . . they stabbed him to death. Do you know just what they were shouting? ‘Kill him, kill him’,” she said.

About ten court officials and lawyers surrounded her and tried to calm her, but she shouted even louder. “For every black child who is shot dead in their bed by gangs. . . you will f****** listen to me,” she said. “You will have to f****** kill me to get me off this stand.” The judge said calmly: “I have heard you.” When Ms Johnson – who is white – was heckled by relatives of the robbers, she screamed: “They are angry because children are being killed in their f****** beds.”

As she was finally removed from the court, she screamed at the people standing at the back of the court: “Stand up for every f****** black kid that’s got shot . . . for every kid jailed in America.” As she was dragged past black spectators in the public gallery, thought to be relatives of the defendants, she yelled at them: “You bastards – you’ve let your f****** black people down.”

Ms Johnson later voluntarily attended a local hospital. It is understood that she is regarded as an exemplary employee of Harrow council and has not been sacked. The court had been told that two of the gang, the Kensal Green Tribe, had been living at a children’s home run by Harrow social services when they committed the robberies. One, Aaron “Redrat” Dennis, 19, had a London Underground map on the wall of his room on which he had marked stations where victims could be found. He was jailed indefinitely yesterday with a minimum of five years after admitting conspiracy to rob and grievous bodily harm.

Sebastien Chidi, 18, who received the same sentence after admitting two woundings with intent and a charge of attempted wounding with intent, said as he was taken from the court: “That’s nothing, man.”

The gang slashed and stabbed their victims and threatened to shoot or rape those who refused to cooperate. They were caught after two of the gang, Donnel Carty, 19, and Delano Brown, 18, stabbed Mr ap Rhys Pryce last year.

Judge Blacksell told Dennis and Chidi: “You preyed on members of the public in a callous and cynical way. You take such benefits as there are from society and then abuse other members of the public, terrifying them.” Ms Johnson’s other client, Harry Bees, 17 – the only white member of the gang – and three other youths convicted of conspiracy to rob and various wounding and GBH charges, will be sentenced today.

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