More than 250 police officers took part in raids aimed at disrupting suspected organised crime groups in Greater Manchester.
Operation Rivercrest targeted homes in and around Heywood, Rochdale.
On Wednesday, 16 men aged between 19 and 49, and a 21-year-old woman were arrested on suspicion of offences including drugs supply, assault, violent disorder, affray, burglary, and robbery, GMP said.
After the arrests, the force said the work was carried out to “take the community back” for the people of Heywood.
The first raids began on Wednesday began at 05:00 BST, when officers smashed through doors and windows of the homes of people believed to hold senior positions within organised crime.
An hour later, a second wave of raids resulted in further arrests.