A 19-year-old man was assaulted with what he believes to be something similar to a metal pole.
The victim was attacked at 5.30pm in Horns Road near to Civic Way, Barkingside on April 23.
He was treated in hospital for a head injury.
Anyone with any information about the incident should call Det Con Hardy on 020 8345 2711 or, if you wish to remain anyonymous, Crimestoppers on 0800 555 111.
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