The teenage boy was attacked in Mayesbrook Park on Tuesday (credit: Google Maps)
A 14-year-old boy was attacked by a large group at Mayesbrook Park just before 5pm on Tuesday, 25 April.
The victim was taken to hospital where his condition has been assessed as not life threatening.
Dagenham police say his family have been informed.
A 15-year-old boy was arrested on Wednesday, 26 April on suspicion of grievous bodily harm [GBH] and possession of an offensive weapon.
He was taken to an east London police station and has since been bailed.
A number of other suspects remain outstanding.
Police are appealing for witnesses or anyone with footage to come forward.
Detective Constable Natalie Anderson of the Met’s East Area Command Unit said: “We know that the victim was attacked by a large group of boys at the scene and I am particularly keen to hear from anyone with footage of the suspects either at the scene or leaving it.”
DC Anderson added: “We know that for young people contacting police can be daunting, but there is the option of contacting Crimestoppers who will pass information onto us for you and they won’t even ask you for your name.”
Anyone with information or footage should call police on 101 or Tweet @MetCC quoting 5373/25APR.
To remain 100% anonymous share your information via the independent charity Crimestoppers on 0800 555 111 or at Crimestoppers-uk.org.
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Tags: Dagenham, Metropolitan Police, Stabbing