Officers investigating the devastating fire at Ratcliffe Mill, on Tong Road, Farnley, earlier this year say they want to speak to Peter Neil Cheetham.
They say they have carried out “extensive enquiries” after he was identified as a suspect but have so far been unable to track him down.
The 23-year-old is local to the Seacroft and East End Park areas but also has connections to Hyde Park.
Anyone who has seen him or has information that could assist the investigation is asked to ring Leeds District CID on 101, quoting log reference 13180036668.
Information can also be passed anonymously to the independent Crimestoppers charity on 0800 555111.
Fire crews were called out to the incident at Ratcliffe Mill in the early hours of Tuesday, January 23.
A total of 10 fire engines were sent to the scene at the height of the blaze.