It happened in Ingrave Road last month (credit: Google Maps)
The 18-year-old was near the cathedral in Ingrave Road when he was attacked last month.
At around 10pm on Friday, 21 June, a vehicle pulled up behind the victim.
Someone got out and hit him over the head with a bottle, leaving him with a concussion.
Police say they have exhausted all lines of enquiry and now need witnesses to come forward.
Anyone with CCTV or dash cam footage, or who has any other information is asked to call Essex Police on 101, quoting the crime reference number 42/97829/19 or Crimestoppers anonymously on 0800 555 111.Tags: Brentwood
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