Cannabis found at a Beeston farm has an estimated annual yield of £200,000, Norfolk Police said.
Officers executed a drugs warrant at the property on Watery Lane in Beeston, near Dereham on Tuesday and found 433 plants in five shipping containers.
Along with the drugs hydroponic growing equipment was also seized.
Trading Standards' Farm Team officers assisted the 16 officers and advised them with their investigations.
A spokesman said because these investigations are ongoing, there are no more details about their involvement in the raid available at the moment.
A 60-year-old man from the Dereham area, a 14-year-old boy from the Attleborough area and a 32-year-old man from the Watton area were arrested on suspicion of cultivating cannabis.
All three have been released on bail until the end of June and July pending further police inquiries.
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