Four women are being questioned on suspicion of drug dealing and money laundering following a raid in Bangor.
Class A controlled drugs were seized along with cash, mobile phones and a knuckle duster in a search on an address on Llys Bedwyr in Maesgeirchen on Friday.
Three of the arrested suspects are from Merseyside and in their late teens – the fourth is a 46 year-old woman from the city who was wanted on an arrest warrant. They remain in police custody.
In another development, two men from Merseyside, aged 18 and 25, were arrested on suspicion of drug supply offences are they were stopped and searched on Beach Road on Friday afternoon. They are also being questioned in custody.
Police are keeping an open mind on whether both incidents are linked.