Dawn raids have been carried out in Surrey, Sussex and London by police in a crackdown on drug dealing.
About 200 officers took part in Operation Erstwhile which targeted 16 properties in Woodhatch, Redhill, Horley, Crawley, Belvedere and Brixton.
Fifteen people were arrested on suspicion of conspiracy to supply class A drugs and about 100 "wraps" of heroin and crack cocaine were recovered.
Surrey Police led the operation aided by the Sussex and Hampshire forces.
Supt Matt Bristow said: "Operation Erstwhile has yet again shown how successful Surrey Police is in identifying and smashing suspected networks of drug dealers who come into the county to supply illegal substances."
The raids were carried out after Surrey Police received intelligence suggesting drug dealers had moved into the county and were supplying heroin and cocaine.
Hydroponics equipment, money and suspected stolen goods were also recovered during the operation.
As well as the 15 drugs-related arrests, one person was arrested on suspicion of breaching bail, one on suspicion of money laundering and two other people were taken to be questioned on suspicion of handling stolen goods.
Two people also received a caution for possession of cannabis.
Supt Bristow said although the majority of the warrants were executed in Surrey they also identified addresses in Sussex and London.
He added: "Clearly this sends a stark warning to anyone thinking of coming into Surrey intent on committing offences that we can, and will, put an end to the misery caused by drugs."