The factory was discovered in a three-bedroom house in Wharfedale Road, Corby, by officers at 11.10am yesterday.

Five police vans were outside the house for several hours while officers examined the property.

Neighbours were upset by the discovery, but not surprised.

Joe King, 78, said: "The house has been a mystery for 18 months. It was up for rent, then last winter I noticed the blinds were always down and the windows open, but you never saw anyone going in or out."

Mr King was going to contact the police until the estate agent letting the property came around to ask him if anyone was living in the property.

He assumed the house was already under investigation so let the matter drop.

Another resident, who did not want to be named, said: "I knew something was going on but even so, when I saw all the police cars I was shocked."

PC Mark Walker, of Corby Central Safer Community Team, said: "We discovered five rooms full of cannabis plants in various stages of maturity. This shows what we can achieve when we work with the community. If you have a cannabis factory, we'll find you."

A 26-year-old Vietnamese man was arrested on suspicion of cultivating cannabis.

On Thursday, Wellingborough police found a cannabis factory containing 300 plants.