A 15-year-old Auckland girl has been found "safe and well", after disappearing from her North Shore home before the weekend.

Mia Cooper was last seen on the evening of December 14, leaving her mother Tracey Stewart "absolutely sick with worry".

She said her daughter disappeared "after being with some people she didn't know very well".

NZ POLICE Police released a CCTV image on Tuesday that was taken before Mia went missing.

Her phone hadn't been used since Friday night and she hadn't been online since just after midnight on the same night, Stewart said.

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In statement, Police said she was found before 2.30pm on Tuesday, but didn't offer any more information about how or where she was found.

Stewart shared the police statement on Facebook, and thanked friends for their love and support.

Earlier on Tuesday, Stewart posted on Facebook that Mia had been in touch and was "alright".

Stewart wrote: "We are in the process of getting her home and surrounding her with the love and support that she needs.

Facebook Mia's mother Tracey said via social media on Tuesday morning they know the 15-year-old is "alright".

"We are forever grateful for the love, support, calls, visits and texts.

"I am sorry for not replying individually to you all but as you can imagine it has been a little overwhelming but know we are eternally grateful for everything."