Two male teenagers, aged 13 and 19, were arrested in the early hours of Saturday morning and are currently being questioned by police in relation to the murder.
An unnamed 15-year-old boy, thought to be a friend of Paul's, is still receiving treatment in hospital for stab wounds.
Metropolitan police are today asking residents in Leytonstone to search their gardens for any bladed instruments or knives used in the attack, while Easter services will pause today in memory of Paul.
The teenager's MySpace music page, which he maintained under the name Hellrazor, has been inundated with messages of condolence from friends.
Speaking yesterday, the Met's Detective Chief Inspector Matthew Horne said: "We understand a large group of youths were involved in an incident in the foyer of Gean Court, a block of flats in Langthorne Road, during which we believe the two victims were stabbed.
"It is believed they then managed to stagger the short distance to nearby Crownfield Road. A number of youths were seen running from the scene.
"We are appealing for anyone who was present during the incident to come forward, along with any witnesses or anyone with information on this appalling crime," DCI Horne added.
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