Three men who ran a £2.6m cannabis farm from a trading estate in Lancashire have been jailed.
The factory, at the Apex Trading Estate in Darwen, was “one of the largest ever found” in the county, police said.
More than 4,500 plants and 27kg of dried cannabis were found during a raid on the site in Lower Eccleshill Road.
The men, all of no fixed address, admitted producing Class B drugs and were sentenced at Preston Crown Court.
Aurel Gjuzi, 32, and Jacek Pieczur, 25, were each jailed for three years, while Sulejman Lloni, 32, was jailed for four years and six months.
The men had been living in the unit, which was powered by underground cables bypassing the electricity supply, police said.
Officers also found £2,425 in cash and a stash of mobile phones.
Det Con Vicky Heys, said the sentences “should send a clear message” to other gangs.
Equipment seized in the raid – including lamps, reflectors, bulbs, transformers and temperature gauges – have since been donated to Blackpool Zoo, the force said.