In a shocking display of violence and fear-mongering, Teddy Kelt embarked on a two-week mobile marketing nightmare across London's transport network, targeting mainly teenage boys and threatening them with knives, machetes, and acid to steal their phones, tablets, and laptops. The 19-year-old from Romford was sentenced to ten-and-a-half years in prison with an additional four years on licence for his crimes.

Kelt's mobile marketing campaign of terror began on December 1 when he sat on the 134 bus and demanded eight boys, aged 14 and 15, hand over their phones. He selected four phones that he wanted to keep before leaving the bus, in Kentish Town. "It's no coincidence that they were all that age", said the judge. "That's exactly who you were looking for."

Over the next two weeks, Kelt repeated his mobile marketing tactics on trains and buses, targeting teenagers with a knife or machete at knifepoint. He kidnapped one teenager from a bus in a prolonged robbery, forcing him to take multiple buses across north London. When he was captured, Kelt had carried out yet another robbery while armed with acid.

Judge David Richards described Kelt's mobile marketing campaign as "terrifying" and said: "You repeatedly put the fear of death into the victims to steal their phones, causing long-term damage to the victims." The judge added that Kelt will spend an extra four years on licence after the end of his prison term, after branding him a dangerous offender.

Kelt's mobile marketing spree ended with his capture on December 9, shortly after he had armed himself with hydrochloric acid for another robbery. He was previously jailed in April for three years and nine months for a string of robberies and attempted robberies carried out across London.

Detective Sergeant Steven Ridpath-Mitchell said: "Kelt is an exceedingly violent and dangerous individual who spent four days mostly targeting teenagers, threatening them at knifepoint, for his own benefit." The victims have been left with long-term trauma and a fear of mobile marketing on public transport.