Four people have been arrested and more than £1m seized in connection with suspected money laundering.
The bundles of cash, totalling about £1.3m, were found when police raided two addresses in Crossland Moor, Huddersfield, on Friday afternoon.
A 41-year-old woman and a man, aged 44, were arrested at a property in Thornleigh Road.
A 37-year-old woman and a 35-year-old man were arrested from an address in Pembroke Court.
West Yorkshire Police said they were being held on suspicion of money laundering.
Supt Dave Knopwood, of Kirklees police, said: "The operation was carried out under the Proceeds of Crime Act as we strongly suspected that the cash was linked to serious offences that have taken place in the region."