Police raided two homes in Montagu Street, Kettering, at 9pm on Friday and were at the scene all weekend.

They had initially been delayed from searching the terraced houses due to fears that a next-door home was structurally unsafe.

A number of residents and businesses had be evacuated and the pavement was cordoned off.

A structural engineer gave the go-ahead on Saturday afternoon and officers recovered about 160 plants from one property, 180 larger plants from the other and equipment associated with the harvesting of the plant.

The discovery is the latest in a series of cannabis factories in the county. The Evening Telegraph reported earlier this year that about 25 factories have been found in Northamptonshire since April last year.

Insp Vaughan Clarke said: "We wanted to take the supply out of the hands of the dealers.

"We had to make sure the buildings were safe and a number of businesses closed at our request because there was question of structural integrity. The pavement was cordoned off as a precaution.

"Drugs are a real priority for us and we will target anyone who commits these offences."

One resident, who did not wish to be named, said: "I saw that a cordon had been set up but we had no idea what it was for.

"It's a complete shock to find out what's been going on down the road – who knows what will happen next."

The third property which was checked by the engineer is not believed to be involved in the operation and has been boarded up.

Officers and forensic investigators returned to the scene yesterday to continue gathering evidence and dismantling the equipment inside.
No arrests have been made at this stage.

A police spokesman said: "We are encouraging people to come forward with information or with any suspicions about potential cannabis factories.

"Information about how to spot them can be found at www.northants.police.uk."