A search is underway for a missing girl who hasn’t been seen since attending a community barbecue in Sydney’s inner west.

Alexandra Zammit-Green, 11, was last seen at the barbecue on Francis St, Glebe, about 5.30pm on Wednesday.

Police were notified of her disappearance when she could not be found or contacted.

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“There are concerns for Alexandra due to her young age,” police said.

Alexandra is described as Caucasian in appearance, about 150cm tall, with a thin build, brown hair and brown eyes.

She was last seen wearing a black hoodie, black tracksuit pants, white shoes and carrying a black backpack.

The 11-year-old is known to frequent Glebe, Dulwich Hill, Parramatta, Guildford, Colyton, Mt Druitt, Blacktown and Toongabbie.

Anyone with information is urged to call Crime Stoppers on 1800 333 000.