A deaf boy with links to Sheffield has been reported missing from home.
Thomas Ashmore-Barbosa, aged 16, from Calow, Chesterfield, was last seen on Sunday.
Police officers believe he may be in Sheffield but he also has links with West Yorkshire.
A Derbyshire Police spokeswoman said: "We are growing concerned for his welfare and want anyone who knows where he is to get in touch urgently.
"Thomas is deaf and anyone who sees him in public is advised to tap him on the shoulder and try to communicate with him as clearly as possible, either verbally or using a writing aid."
Anyone with information should call Derbyshire Police on 101.