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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An inquest is due to open into the deaths of five friends who drowned during a day trip to Camber Sands in East Sussex last summer.
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