Officers are encouraging youngsters to only trick or treat at houses they know, ideally with an adult supervising.
Drug Link To Portsmouth Woman's Death?
The death of a 28-year-old woman may be related to substance misuse, police have said.
Sasha Barber died at an address in Clarendon Road, Southsea, Hampshire, on Saturday.
A 20-year-old man was arrested in connection with her death but was later released without charge.
A powder found at the flat is being analysed by police to establish what it is and whether it is connected to her death.
Miss Barber's next of kin have been informed, according to a Hampshire police spokesman.
He said: "We can confirm substance misuse is being investigated as part of inquiries to establish the woman's cause of death.
"A post-mortem examination and toxicology tests will take place in due course as police prepare a file for HM Coroner.
"Powder was seized from the address. This is being analysed to confirm its contents and identity.
"The death is not being treated as suspicious.
"At this time, there is no evidence to suggest a crime or any links to other deaths or offences.''
It is understood that police do not believe the death is connected to ecstasy use.
Miss Barber is understood to have worked at the Spinnaker Tower at Portsmouth's Gunwharf Quays waterside retail and leisure complex.
The Queen, Duke of Edinburgh, Prince of Wales, Duchess of Cornwall visit Poundbury in Dorset.
South Central Ambulance Service hopes it'll help save lives, of people suffering cardiac arrest.
As the evenings start getting darker, officers are urging riders to use lights and wear reflective clothing.
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