Nine men and one woman were arrested in early morning raids across Newcastle.
The co-ordinated strikes at 15 addresses were part of Operation Magnet, a long-running investigation into drug dealing by an organised crime group in the city.
The men, aged between 22 and 46, were all arrested on suspicion of conspiracy to supply controlled drugs.
A 46-year-old woman was arrested on suspicion of attempting to conceal criminal property.
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