A teenager found dead in Woodford Green has been named as 18 year-old Luke Harwood from Havering.
His body was discovered by police near Broadmead Fields on Monday night.
Four men and a woman, who were arrested in connection with his death, are being interviewed by police.
A post-mortem examination is expected to take place today.
Police are particularly interested in hearing from anyone who saw a blue Fiat Punto in Courtland Close - or activity near the bridge in Chigwell Road (close to the Jet petrol station) - on Sunday or Monday.
More top news
Firearms officer Martin Finney was awarded the George Medal, Britain's second highest civilian decoration.
Members of the RMT union who work on the Central Line will walk out at 9pm on Wednesday.
Southeastern was hit after a freight train derailed causing travel chaos for hundreds of thousands of passengers.