Police raided a derelict building looking for suspected stolen car parts.
Officers executed the search warrant at a premises on Huddersfield Road, Dewsbury, at around 12.30pm on Tuesday.
They seized dozens of car bumpers, doors and engine parts.
Police said the value of the suspected stolen items is unknown.
Two men, aged 54 and 21, were arrested at one of the units on suspicion of burglary.
A 35-year-old man was arrested from a second unit on suspicion of theft of motor vehicles.
Det Insp George Bardell, of Kirklees CID, said: “The early evidence suggests that stolen vehicles from West Yorkshire and the north of England may have been handled here.
“We were alerted to the premises following intelligence received directly from the local community, following the increased policing presence over recent weeks.
“Our investigation is at an early stage and we would encourage anyone in the area who has any information to come forward.”
Anyone with information should call Kirklees CID on 101.