Police are hunting Stuart Hazell, the step-grandfather of missing girl Tia Sharp, after a body was found at her grandmother's property.
Police discovered the body at the house of the missing girl's grandmother Christine Sharp at 20 The Lindens, New Addington.
Authorities have warned the public not to approach Mr Hazell.
A murder inquiry has been launched and Tia's family has been informed of the discovery.
Earlier police cordoned off her grandmother's house and started a full forensic search of the property.
Not long after forensic officers entered the house, the body was found, says Sky's crime correspondent Martin Brunt.
Earlier, Christine Sharp, 46, left the house with police as search dogs scoured a wooded area 400 yards from her home.