St Julian's food stores have been advised to be careful who they sell flour and eggs to this Halloween, amid concerns that the items might be used to vandalise houses. 

The warning was sounded in a letter sent by the St Julian's local council and community police, as children and adults alike gear up for a weekend of trick-or-treating. 

The custom sees children and people dressed up in Halloween-themed costumes travelling from house to house, asking for treats.

Residents who decline to do so risk some mischief such as having eggs, flour or shaving foam thrown at them or their house.

Times of Malta readers have been complaining of such stunts for over two decades, with the newspaper reporting in 2002 that a strong police and warden presence in Swieqi confiscated 'ammunition' before youngsters started their visits.

The trick-or-treating custom has since spread to other localities, including Pembroke, St Julian's, Żabbar, Żurrieq and Żebbuġ, where residents are encouraged to decorate their houses and participate in the event. 

But the St Julian's local council is not taking any risks this year.

In collaboration with the locality's community police, it is urging businesses to be "vigilant with the sale of certain products, such as eggs and flour".

"In recent years, these products have been used wrongly and residents and their property have suffered damages. Thus we urge you not to sell products to persons (especially youths) who normally don't buy these products," they said in a letter distributed to business owners in the locality and shared with social media users.

On social media, the community police also urged parents and guardians to "educate your child that egg throwing/fighting with eggs or with any other item is prohibited, especially during this Halloween period".