A man has been arrested in Bognor Regis on suspicion of possession of a Class A drug with intent to supply.
Posting of social media, Arun District Council said: "Targeting drugs in #Arun remains our high priority. Yesterday we arrested a male in #BognorRegis town centre for Possession with Intent to Supply Class A Drugs.
"They remain in custody at this time whilst investigations continue."
Arun Police later commented that the drugs had been 'preliminary tested' as part of the investigation and the results of the tests suggested they were a suspected opioid substance. The substances will be going for full forensic analysis so the police will be able to tell categorically what the drugs are, police said.
A picture posted as part of the post shows 42 separately bagged substances.