A dozen people have been arrested in a series of early-morning raids targeting suspected drug dealers.
Officers swooped on houses at 7.30am today, including in Trimdon Village.
Seven men and three women, aged between 25 and 50, were arrested in the raids, which also took in addresses elsewhere in County Durham, Darlington and North Yorkshire.
Officers from West Yorkshire Police also made a further two arrests in Bradford on behalf of Durham Constabulary.
All those arrested are now in custody at police stations across Durham and Darlington, with the exception of the Bradford suspects, who are being held in West Yorkshire.
All were detained on suspicion of being concerned in the supply of Class A drugs.
This morning's action was under the banner of 'Operation Sledgehammer', the force's long-running campaign to tackle serious and organised crime.
Det Insp Nicola Lawrence said: "This operation was aimed at targeting those we suspect to be involved in organised crime, especially the supply of drugs.
"We are very satisfied with the results and with other inquiries in hand, we expect to make more arrests over the next few days.”
Addresses targeted across the Darlington area include Clifton Road, Hundens Lane, Napier Street and Pemberton Terrace in Middleton-St-George.
Anyone who has information about drug dealing or any other criminal activity in their area is urged to call the independent charity Crimestoppers on 0800 555111.