The grandmother of missing 12-year-old Tia Sharp has made a desperate plea for the child to contact her family and "come home".
Police have said they are becoming increasingly worried about the girl who disappeared three days ago.
Tia was last seen leaving her grandparents' home where she had stayed the night in New Addington, south east London, at around midday on Friday after telling relatives she was going to the Whitgift Centre in Croydon town centre.
Her grandmother Christine Sharp told LBC radio: "Come home. She's very much loved, very, very much missed, just contact any of us whatever way she can."
Detectives are continuing to look through hours of CCTV footage for a clue to her location.
Her disappearance has been described as being "completely out of character".
A number of possible sightings have been reported to police, who believe she had a small amount of cash with her, but did not have her mobile phone.
Tia also did not have her young person's travel card with her. However, some bus and tram drivers let children travel without one.
Tia Sharp disappeared last Friday Sky correspondent Martin Brunt said: "According to family members, Tia told her grandfather she wanted to go into Croydon five miles away to buy some shoes.
"According to her grandmother, her grandfather gave her some money for the shoes and she left the house and was just going to walk the 100 yards or so away down to the road that runs at the bottom of the estate where there are any number of buses that go into Croydon.
"She had done that journey a number of times, according to her grandmother, but never alone.
"The increasing concern is that she may have got into a vehicle. The big question is - is this a vehicle driven by someone she knew and was a friend or is it somebody who might be hostile in some way to her?
"That's where the focus of the investigation is at the moment. There are no clues at all to what happened."
Detective Chief Inspector Nick Scola reiterated appeals for information and said he is particularly keen to hear from anyone in The Lindens area of New Addington who has information.
He said: "We are currently examining CCTV; at this time we have found no trace of Tia on the footage examined thus far but this is an ongoing process which will take time.
The child is 4ft 5in tall and wears glasses "We have spoken to Tia's family and some of her friends and Tia has never gone missing before and it is extremely out of character for her not to return home or contact her friends or family."
Mr Scola went on: "There has been a lot of activity on Twitter from Tia's friends and, whilst we would want to ensure that images of Tia and details of her disappearance are spread far and wide, we would urge people using social media to include the Incident Room number rather than their personal numbers.
"We have received a number of purported sightings but none are confirmed as Tia at this time."
He added: "I am appealing for any bus or tram drivers in the Croydon area who recognise Tia's description to contact us.
"Of course if Tia herself is able to contact her family or the police, we urge her to do so."
Tia is white, 4ft 5in and slim, and was wearing FCUK glasses.
She was dressed in a yellow bandeau top over a white bra with visible cross straps, light grey leopard print leggings and black and pink Nike high top trainers.
She is known to frequent the Croydon, Mitcham and Wimbledon areas.
Anyone who has seen Tia or knows of her whereabouts should call Merton Police on phone number 101, quoting reference 12MIS025216.
