BIN liners stuffed with cannabis were found by undercover police.
They found 23 bags full of the class-B drug inside the back of a van on the Ashley Industrial Estate, Flushdyke.
Two men fled from the van after being approached by Special Constables Chris Coombs and Paul Rodgers, of the North West neighbourhood police team, in the early hours of Sunday.
Police believe the cannabis had recently been harvested.
They are hunting for two male suspects who fled the van, which was a hire vehicle. One of the men had an Irish accent.
In Normanton, NPT officers raided a cannabis farm of up to 20 plants on King Street on Saturday, June 30.
And on Sunday, July 1, they found four plants in a house on Cypress Road.
Two men were arrested in connection with the two separate incidents and released on bail pending further enquiries.
Anyone with information should call police on 101.