Shops will be asked not to sell children flour, eggs and other items to avoid any Halloween horrors this year.

Thames Valley Police are making their annual appeal not to make Halloween too horrible, with children and parents being warned not to give elderly neighbours a real fright during Halloween.

Police staff are visiting schools and working with shops to make sure trick or treating does not turn into antisocial behaviour or vandalism on October 31.

Crime reduction adviser Lesley Nesbitt said: "We want children to have fun at Halloween, but we also want to make sure they understand that some members of the community do not look forward to this time of year.

"Elderly residents, vulnerable members of the community and people who live alone can be intimidated by unexpected knocks on the door or loud noises outside."

Police officers, crime reduction officers, and police community support officers in south Oxfordshire will be asking shops not to sell children flour, eggs and other items that are sometimes thrown at cars and buildings during Halloween.

A police spokesman added: "Shops will be given posters to display which say they reserve the right not to serve children with such items."

Trick or treaters will also be warned that damage to property is a criminal offence, and that the person responsible could be arrested.

As well as school visits, letters will be sent to parents of primary school children, setting out guidelines for Halloween celebrations.

Residents who do not want to take part in trick or treat can put up a special poster which is available from police stations or the police website, www.thamesvalley.police.uk There will also be extra officers on patrol during Halloween evening.

A police spokesman said parents should try to find out beforehand which neighbours did not mind a trick or treat visit - and only call at those homes.

He added: "Parents are also asked to discourage older children from going trick or treating. As a rule if they are old enough to go on their own then they are too old for trick or treating."