A further four people have been arrested afte police raids took place in Newcastle at dawn as part of an investigation by Northumbria Police.
The total of people who have now been arrested during Operation Magnet now stands at 14.
12 men have been arrested on suspicion of conspiracy to supply controlled drugs, and two women have been arrested on suspicion of attempting to conceal criminal property.
They are all currently in police custody.
"Fifteen addresses were visited today and 14 people have so far been arrested. This was clearly a crime group working together and this operation has significantly disrupted that group's activities.
"I would like to thank our local communities who supply us with information and tell us what is happening in their local area. It means activity like this can take place. This is what we do with that information and how seriously we take it.
– Chief Superintendent Gary Calvert, Newcastle Area Commander
"Operation Magnet will continue and Northumbria Police's message to anyone who is involved in the supply of drugs or organised crime is simple - once we find out who you are you can expect a similar visit by police."