A quantity of suspected class A, B and C drugs were seized along with cash and drugs paraphernalia.
Officers from Waterside Neighbourhood Policing Team along with colleagues from the tactical support group carried out searches in the waterside area of the city over the weekend.
A PSNI spokesperson said: "A quantity of suspected class A, B and C drugs were seized along with cash and drugs paraphernalia.
"A male person has been arrested and is in custody assisting with our enquiries.
"The Police Service of Northern Ireland, through Op Dealbreaker, continues to tackle the harm caused by illegal drugs, illicit prescription medication and their supply, use and misuse in Northern Ireland.
"If you have any information in relation to the supply, use and misuse of drugs in your area please contact your local police station or contact crime stoppers anonymously on 0800555111."
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