The family of a missing 34-year-old say it is "out of character for her to leave her daughter".
Natalie Gallagher, originally from Derry, was last seen on Friday March 18 at 4.30am in Belfast.
She was seen wearing a cream coat, a jumper and dark coloured jeans on Great Victoria Street.
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Police say they are "urgently trying to make contact with Natalie", who has now been missing for two days.
A PSNI missing persons appeal read: "If you have any information please contact 101 quoting reference 2242 of 19/3/22. If emergency 999. You can also make a report online."
A family friend told Belfast Live: "Natalie was last seen on March 18 and it is out of character for her to leave her daughter. She is from Derry originally and her family are really worried about her."
In an unrelated appeal, police are also appealing for the public's help in locating a missing man, from the Crumlin Road area of Belfast.
Alastair Adair was last seen at 12:00 on March 18 wearing a dark grey beanie hat, light grey jumper, black trousers, dark grey shoes and carrying a black holdall bag.
Police said: "Alastair is known to frequent the Newtownards area. If you have any information which could assist us in locating him, please contact 101 quoting reference number 842 of 19/3/22."
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