Police said £2,000 worth of luggage containing Transformers figures and a clarinet were brazenly stolen from a train in the run-up to Christmas.
British Transport Police said the belongings were taken on December 20, 2019, at about 9.45pm, on a train travelling towards Wigan.
The suspected thief then boarded a train towards Liverpool Lime Street.
The luggage contained a Yamaha clarinet valued at £1,000, a laptop and a number of Transformers figures.
In a statement, British Transport Police said: "Officers would like to speak to the man in the image who was pictured at Wigan North Western station. They believe he has information that could help their investigation.
"The man was then seen to board a service heading towards Liverpool Lime Street.
"Anyone with information is asked to contact BTP by texting 61016 or by calling 0800 40 50 40.
"In both cases, quote reference number 1900109761.
"Alternatively, call Crimestoppers anonymously on 0800 555 111."
