Officers in Sheffield are appealing to the public to help find a 12-year-old who goes by the name of Mark.
The individual, with no known surname, was last seen around 7pm on Monday 28 November in the area of Parsons Cross, Sheffield.
Mark is described as a white, 5ft tall, slight build individual with dark brown hair.
He was last seen wearing a black puffer jacket with a PlayStation logo on the front, dark jogging bottoms and black, white and blue Nike branded trainers.
Officers are becoming increasingly concerned for Mark's welfare and wish to speak to anyone who has seen him.
Police say the 12-year-old also has links to Derbyshire.
As part of the ongoing investigation, a 46-year-old man has been arrested on suspicion of child abduction and remains in custody.