By Dan Parkinson
BBC News, Leytonstone
On the estate where Paul Erhahon lived, residents had become concerned about a developing gang culture and a network of local rivalries among teenagers.
Police investigations into Paul's death are continuing
Late last year residents created their own group, the Cathall Community Safety Group, to try to tackle the problem.
Jane Brueseke, one of the founders of the group, said police had privately voiced fears to her that someone would soon be seriously injured.
She said police recently stopped a 13-year-old who was found to be carrying a gun.
"I don't like to use the word 'gangs' but the young people were hanging around in really big groups," she said.
"There was lots of anti-social behaviour. They were mainly intimidating people in their own peer groups, but passers-by and residents were being intimidated as well."
Ali Imran, 17, said many of the young people carried knives and he himself had been threatened several times.
"I've had knives pulled on me around here before now," he said.
"It's getting worse and worse. They think it's normal to carry knives, it's like a game to them, but look at what has happened - someone has been killed."
Police have said Paul Erhahon's killing may be gang-related, but they are keeping an open mind.
A rivalry had existed in the area - a mile from Leytonstone town centre - between the Cathall estate and the Avenue estate, where Paul lived.
The estates are just half a mile apart, separated by a park which, according to Ms Brueseke, had become a no-go zone.
On Saturday the street where Paul was found with stab wounds was sealed off along with surrounding roads.
Police helped place floral tributes near the murder scene
A blue-and-white police tent had been placed over a section of pavement just yards from Paul's home.
The area is dominated by Blackthorne Court, a seven-storey complex of council flats.
Mrs Brueseke said the area is classed as highly deprived and received special government funding.
"There is nothing to do here for young people over the age of 14," she said.
"It is a transient community with a large immigrant section.
"We wanted to try and tackle the problems and get to the bottom of what was happening."
Paul had been a quiet pupil at school.
"When Paul was at school he used to be a very calm person; he was never in trouble," said Ali Imran.
"Then he started hanging around with other youngsters on the estate and things changed."
Ali said Paul had been in a group called The Funeral Soldiers.
Paul can be seen with some of his friends in a rap video posted on the website YouTube. He appears under the name Hell Reiser.
He is among the Funeral Soldiers in the three-minute film, made in the streets in the area in which he was found stabbed.
The video can also be accessed through his page on the communities website MySpace, where he talks about his musical ambitions and of DVDs and mixtapes he has contributed to.
Within hours of news of his death, friends had left tributes on the page.
Paul Erhahon appeared in a video on the YouTube website
Many messages simply read "RIP" but others include pleas for an end to the type of incident, which has claimed the lives of more than six teenagers in London this year.
"People need 2 put down da gunz and knifes!!" a message from Explicit reads, while Hektik says: "When is this gonna stop, another 1 gone, and what for ??? for rep??? its waste".
An anonymous message refers to last month's killing in Plaistow, east London, of Adam Regis, said to have attended the same school as Paul.
Schoolfriends also recall Paul.
Jennifer writes: "R.I.P paul im gna miss you still im gna remember everything u used to say to me at school nd all da fun we had."
The longest message, posted anonymously, is from a friend who recalls times playing football together.
"Those are days that we should still have been having," it reads.
"One day everything is all gravy... next... you're gone... ged just 15... you should never have died before you got to live... the only comfort i have right now is that you've gone to a better place... nobody deserves to live in a world with people who think that have the right to kill."