Police are growing increasingly concerned for a 15-year-old girl missing for 14 days.
Madison, known as Maddie, vanished on April 26 after leaving her foster parents’ address in Southmead, Bristol, to say she was going to the shops.
She has been known to use social media to meet people who might give her money and a place to stay, Avon and Somerset Police said.
She is described as white, about 5ft tall and of an average build with shoulder-length brown hair.
On Tuesday, officers were going door-to-door in the Southmead area making inquiries, and also giving out leaflets with Maddie’s picture on them, a spokesman for Avon and Somerset Police said.
Investigators have also released CCTV of the last known sighting of her.
The clip, filmed on April 26 on Stanton Road, Southmead, was recorded at 2.34pm and captures only her feet.
Detective Inspector Stuart Toms said: “(Maddie) is a vulnerable teenage girl who is at risk of being exploited and we urgently need the public’s help to locate her and make sure she’s OK.
“Maddie – if you see this please let someone know you’re safe and well. Your family, foster parents and friends are worried about you.”
He added: “Maddie is very active on social media but she changes her accounts frequently.
“As well as appealing to anyone who might see Maddie to contact us, we’re also keen to hear from anyone who sees her online to get in touch.”
Anyone who sees Maddie is asked to call 999, quoting reference 5222098703.
Those who have information about her whereabouts or spots her online is asked to call 101, quoting the same reference number.