A 13-year-old girl has vanished from her home in Sutton-in-Ashfield.
Ellie-Jo Miller was last seen at about 6.30pm on Monday and has not contacted family members since then.
She is white, around 5ft 3in tall and has shoulder-length light brown hair.
Ellie-Jo was wearing a black top, black jeans and black and red Nike trainers when she was last seen.
A Nottinghamshire police spokesman said: "She may be using the local rail network so officers are appealing to commuters and other train users to make contact if they believe they may have seen her.
"It is thought she may have travelled to the Sheffield area.
"If you believe you may have seen her, please call police on 101, quoting incident number 973 of 4 July."