A fourth person has been charged with the murder of girl scout Jodie Chesney, who was stabbed in a park in Harold Hill.
Jodie, 17, who lived in Dagenham, was attacked as she listened to music with friends in Amy's Park in St Neot's Road on March 1.
Police said a 17-year-old boy from Barking was charged today with murder.
He was also charged with possession of a stun gun and he will appear at Barkingside Magistrates' Court tomorrow.
He was first arrested on March 10 and initially released under investigation.
Two men and a boy have already been charged with her murder.
Manuel Petrovic, 20, of Highfield Road in Romford, Svenson Ong-a-kwie, 19, of Hillfoot Road in Romford. and a 16-year-old boy, who cannot be named, are due to face trial at the Old Bailey in September.
Two other people arrested on suspicion of assisting an offender - a 50-year-old man and a 38-year-old woman - have been released under investigation.
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