THIEVES stole a piece of dyeing equipment worth £40,000.
The 12ft by 8ft stainless steel dyeing vessel was taken from Huddersfield Dyeing Company on Canal Street, off Leeds Road, Huddersfield, between 7.30pm on Thursday and 5.30am on Friday.
The thieves had forced padlocks on a gate to get into a compound and steal the vessel from a vehicle.
Sgt Tim O'Sullivan, of Huddersfield police, said: "The thieves would have needed a large vehicle to steal this equipment.
"People may have spotted them but thought they were genuine workers at the time."
Anyone with information should contact Pc Michelle Finch on 01484 436659.