Investigating officer Det Insp Andy Howard said: “We are keen to talk to anyone who was in Vulcan Drive yesterday in the early evening and saw anything suspicious.
“We are not looking for anyone else in connection with this incident but are trying to piece together what happened.
“In particular, we would like to speak to a group of youths who were outside at about the time of the incident."
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The High Court has agreed to a Sussex Police request for access to footage of the Shoreham air crash, but has rejected two other requests.