The uncle of missing school girl Tia Sharp has made an emotional plea to the 12-year-old, urging her to "come home".
Tia has not been since she left her grandmother's home in New Addington, south east London, around midday on Friday.
David Sharp, 28, who spoke at a news conference in Scotland Yard, also urged anyone who has any information about where his niece may be to come forward.
Mr Sharp was supported by two friends at the news conference. All three wore "Missing" T-shirts with a photograph of Tia printed on them and an appeal for information.
Detective Chief Inspector Nick Scola, who is leading the investigation, said there has been a "good response" from the public.
He said 55 sightings of the young girl have been reported so far, but added that none of them were substantiated.
Mr Scola said the last person to see Tia before her disappearance was the partner of her grandmother, Christine Sharp.
Police believe the missing 12-year-old had a small amount of cash with her, but she did not have her mobile phone or a travel card.
Mr Scola said he did not have any information about when the girl's phone was last used.
He added that detectives are continuing to sift through hours of CCTV footage for a clue to her location.
Tia, who has not gone missing before, disappeared after telling relatives she was going to the Whitgift Centre in Croydon town centre. The local community have rallied around her family, printing out homemade flyers to help locate Tia.
Mr Scola reiterated appeals for information and said he was particularly keen to hear from anyone in The Lindens area of New Addington who had information.
Tia 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 at the time of her disappearance.
Celebrities including Lennox Lewis, Peter Serafinowicz and Jessie J have been posting messages on Twitter appealing for information.
Tia 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.