Thirteen people were arrested and around 1,000 cannabis plants seized when police smashed a major drugs farm in the Black Country.

The sprawling warehouse in Wolverhampton where the discovery was made was packed with sophisticated watering and lighting systems to speed the growth of the crop. Officers swooped on the unit – formerly Flynt Leisurewear and M&B Textiles – in Whitmore Reans after loud crashing and banging was heard inside.

The noises prompted fears the cannabis operation was being dismantled and closed down. Neighbours said police had been tipped off several weeks earlier about suspicious activity at the Craddock Street building.

Mango Khan, aged 34, who lives in nearby Dunstall Road, said: “People had heard loud noises coming from inside the factory and called the police, although they had first been told about strange goings on at the place around six weeks earlier.

“About eight police vehicles arrived around midnight and raided the place, arresting a load of people.

“It used to be a clothing factory but that shut down several years ago and the unit had been offered to let. I have no idea if it had been rented out under the guise of a legitimate business.”

More than 12 hours after the raid, carried out in the early hours of Saturday, three skips were brought to the scene along with two police vans and a panda car as specialist officers wearing white protective overalls carried plants out.

West Midlands Police spokesman Steve Garey said today three men aged 27, 35 and 40 have been charged with cultivating cannabis and 10 others were still being questioned today.

A string of Black Country drug factories have been closed down in recent months with at least nine raided in Sandwell alone and one of those held a haul of cannabis worth an estimated £1 million on the streets.

They included two warehouses and a shop in Cape Hill feared to have been used as the distribution centre. Fifty cannabis plants reportedly worth over £100,000 were found in a rented house in Gough Street, Willenhall, while 60 were unearthed in the loft of a house in Vale Road, Netherton.