The police have released CCTV pictures showing nine-year-old Shannon Matthews shortly before she disappeared three days ago.
Shannon, from the town of Dewsbury in West Yorkshire, failed to return to her home after a swimming trip on Tuesday.
The pictures show her entering and leaving the Dewsbury Sports Centre Swimming Pool in West Yorkshire.
Police are also checking out reported sightings after several people have claimed to have seen her.
Police say she had told some of her friends that she didn't want to return to her family home, and that she had written on her bedroom wall that she wanted to see more of her father.
Shannon has been missing since Tuesday
Shannon has not run away before and her mum has made an emotional appeal for her daughter to come home.
A man has reported seeing Shannon just a few hundred metres from her home the morning after she disappeared.
A police spokesman said the sighting was one of a number his team of 60 detectives were investigating.
It's important to remember that incidents like this are very rare.
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Call this free helpline 0808 800 7070 or email runawayhelpline@ missingpeople.org.uk
Shannon is 4ft 1in and slim, with shoulder-length and medium-brown hair. She has blue eyes and freckles.
She was wearing a black school jumper with a school logo on it, a white T-shirt, black trousers and a black, waist-length coat with fur round the hood.
If anyone has any information about Shannon, they should call the Runaway helpline which is free on 0808 800 7070.