Three people have been arrested during armed police raids of houses in Stockton this morning (Thursday, March 28).
At 7am officers from Durham Constabulary and Cleveland Police descended on four addresses.
They were backed up by teams from the National Crime Agency and the North East Regional Organised Crime Unit.
Three men were arrested on suspicion of conspiracy to commit arson, possession of a firearm with intent to endanger life and participating in the activities of an organised crime group.
Last week, a total of 11 people were arrested in connection with the investigation.
Officers carried out a series of co-ordinated strikes across Bishop Auckland, Shildon, Crook and Sherburn.
All 11 individuals were released on bail with strict conditions, while further enquiries are carried out.
A Durham police spokesperson said: We are moving at pace on this investigation and will continue to take opportunities to dismantle, disrupt and destroy these enterprises.
Today’s activity sends a clear message that organised crime has no place in our region, and we are committed to pursuing those that operate within these networks.
Anyone with information on potential criminal activity in their area should call us on 101 or via Crimestoppers anonymously on 08000 555111.