POLICE are leading the fight to close down the cannabis factories used to grow drugs on our doorstep.

Since August last year, officers in Greenwich borough have raided 49 homes in residential areas and taken more than 10,000 cannabis plants.

In Woolwich alone, more than £4m worth of the Class C drug has been seized.

Greenwich's Superintendent Carol Grigg says clamping down on the problem is vital in preventing further crime.

She said: "Cannabis feeds and pays for a lot of other crimes. It generates so much revenue.

"It is an area of major concern to the community and it is important we respond to the problem."

Most of the police raids, which began on August 1 last year, have taken place in the Woolwich or Plumstead areas.

Sergeant Dale Openshaw, who has been involved in 15 of the 49 closures, says the cannabis factories usually follow a familiar pattern.

They are often rented properties looked after by a caretaker, with irregular visitors coming to and from the house.

The rooms inside are well heated and ventilated to create an ideal growing environment.

Sgt Openshaw says residents should look out for other sure signs, such as unusual smells and blocked windows.

Officers have recently started to take an information board with them on the raids, telling residents a cannabis bust is taking place in the area.

Sgt Openshaw believes this is an important tool in reassuring the public.

He added: "When we do these raids and there are lots of police around, people sometimes think there has been a murder.

"It can create a fear of crime, where residents think their area is going downhill.

"The sign lets them know what is happening and is designed to allay the public's fears."