A cannabis farm growing plants worth up to £70,000 has been smashed in a flat above a parade of shops.
Police seized around 200 plants from the flat on Hawkesbury Drive in the Kingsfold area of Penwortham.
A 37-year-old local man was arrested on suspicion of growing the Class B drug with intent to supply.
A Lancashire Police spokesman confirmed officers also seized a large amount of equipment during the raid at around 9.15pm on Friday.
Officers returned to the property to remove a large quantity of cannabis plants and equipment on Saturday morning.
A local resident, who asked not to be named, said officers had been at the scene throughout Friday night.
She said: “They had to load up two big vans with all the plants and equipment they brought out.
“No-one around here knows who the man who lived in the place was or what he was doing up there.
“It is quite a shock to think that something like that is going on right on your doorstep.”
A local trader said she had been left shocked by the quantity of the drug being grown in the property.
She said: “You would think you would notice something like that.
“When the police went in and started bringing out all these plants and equipment, I could not believe how much there was.
“How they managed to get all that in there without anyone around here noticing, I do not know.
“It is really shocking.”
Another local trader said the flats were run by a housing association and were not connected with any of the shops in the parade beneath them.
He said: “The police were in there all (Saturday) morning taking stuff out.
“It looked like equipment and possibly plants wrapped up in plastic bags.”
The raid is the latest in a sustained crackdown on drug factories by Lancashire Police which has seen more than £8m of drugs seized from 485 cannabis farms in the past year.
In Lancashire, in just over a year, 20,603 plants have been found in the factories.