A major police operation during Friday (27 July) shut down a suspected cannabis farm in Ashton-on-Ribble.
Dozens of police officers swooped on the former China House restaurant in Aqueduct Street.
Two men were arrested on suspicion of cannabis cultivation.
A 54-year-old man and a 35-year-old man remain in custody.
Preston Police surrounded the building from around 9am on Friday and were joined by teams from Electricity North West.
Read more: Asbestos dumped outside former Preston restaurant
What was the Lime Kiln pub for many years became the troubled Chinese restaurant, which shut down in June 2014.
Its former owner appeared in court in May 2015 and pleaded guilty to four health and safety breaches.
An inspection of the premises found gas bottles stored in the cellar and a cooking range which had been leaking gas.
Following the Magistrates Court hearing a senior environmental health officer for Preston City Council Jonathan Cruickshank said: “Due to timely interventions with our partner organisations, fortunately no-one was injured. If the illegal gas works had not been found it is likely that the consequences could have been a fire or explosion that could have seriously injured or killed staff and members of the public.”