A large barn that burned to the ground Monday morning in Surrey used to house a marijuana grow operation, but the landlord says it's no longer active.

Six fire crews were sent to battle a fully-involved blaze at the Mihn Hien Mushroom Farm in the Port Kells area.

Billows of black smoke were visible for several kilometres.

The landlord of the property told CTV News that the tenants operating the grow-op removed all of their marijuana a few weeks ago and doesn't believe there was any on the scene.  He believes arson may be involved.  

Mounties are now involved in the investigation.  No one was injured in the blaze.