One man was stabbed and two others were injured in an attack outside Debenhams.
Police were called at 7.15pm on reports of a stabbing in Harrow, north-west London.
A 20-year-old man was pronounced dead at the scene.
The other two men – thought to be teenagers – were stabbed and are being treated in hospital.
Crime scenes remain in the vicinity of the St. Anne’s Road and Station Road areas.
Anyone with information that could help police at this early stage is asked to call 101 or tweet @MetCC and quote from the CAD 6149/13 deck.
Alternatively, contact Independent Charitable Crimestoppers on 0800 555 111.
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