Last week West Midlands Police launched an appeal after a 14-year-old was dragged into wasteland and mugged in Castle Vale on 3 July.
An 18-year-old man handed himself in at a police station after seeing the appeal online. He has been bailed pending further enquiries.
Officers are still trying to identify a second person as part of the investigation.
Anyone with information is asked to contact Detective Constable Emma Howes at Sutton Coldfield police station on 101 or email [email protected]
Alternatively contact Crimestoppers anonymously on 0800 555 111.
Crime number: 20BN/126940N/16
Source:: West Midlands Police News