Two teenagers were stabbed during a ruckus at a party in Manor Park last night.
The victims, both aged 17, were attacked in the stairwell of a block of flats in Daines Close.
Dozens of police officers were called to the scene at around 11.20pm.
The victims were taken to hospital and one underwent surgery to determine the extent of his wounds.
Neither received life-threatening injuries, Scotland Yard said.
The suspects are believed to have fled the scene as police arrived.
The entrance to the block remains sealed off this morning, with officers standing guard outside.
No arrests have yet been made.
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