An elderly woman with dementia who vanished from Western Sydney in the middle of the night has been found safe.

The 77-year-old was last seen on Bombala Crescent in Quakers Hill about 1am on Saturday and had not been seen or heard from since.

Police were alerted to her disappearance and began inquiries to find her.

There are serious concerns for the woman’s welfare as she lives with dementia.

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Police confirmed on Saturday afternoon that she had been located.

“Riverstone Police thank everyone who shared our appeal to find her,” police said.