Brandon Wright, 17, is wanted in connection with an armed robbery in November 2021.
A man was pulled into an alleyway and stabbed with a machete in Chapel Street, Chorley.
Wright has since failed to appear in court, prompting police to launch a public appeal.
The 17-year-old has links to Preston city centre, Ribbleton and Bamber Bridge.
If you can help, call 101 or email [email protected]