More than 20 police officers raided three city addresses and arrested two women on suspicion of possession with intent to supply Class A and B drugs.
At 7am on Wednesday warrants issued under the Misuse of Drugs Act 1971 were carried out at the properties in Moulsecoomb Way, Brighton.
Quantities of what are believed to be Class A and B drugs, comprising white powder and herbal cannabis, cash, and drug-related paraphernalia, were seized and two women aged 61 and 41 were arrested on suspicion of possessing drugs with intent to supply.
They are currently in custody for interview and further enquiries.
Inspector Roy Apps said: "This operation was necessary as information regarding the unlawful supply of drugs could not be ignored.
“Substance misuse is dangerous and those supplying need to be tracked down and stopped.
“This is a positive step towards reducing the amount of drugs on our streets and will hopefully deter others from engaging in drug supply."