Three people have been arrested as part of an investigation into insider dealing by finance regulators.
The Financial Services Authority (FSA) confirmed that working with Cheshire and Lancashire police it arrested two men, aged 42 and 43, and one woman, aged 35, on 1 March.
It also said searches of three properties in Northwich and Rossendale were carried out.
Those arrested will now be questioned as part of the investigation.
No charges have been brought and the FSA is refusing to confirm any further details, including names.
Insider dealing can carry a seven year prison sentence.
The FSA is currently prosecuting 16 people on allegations of insider dealing.
It has already successfully pursued 11 convictions for the outlawed practice.
On 15 December Rupinder Sidhu, a management consultant, got a two year jail sentence for 22 counts of insider dealing after the FSA brought a case to Southwark Crown Court.
"This is another step in our fight against market abuse," Tracey McDermott, acting director of enforcement and financial crime at the FSA, said at the time.