It followed raids on properties in Inverness and Liverpool.
Police said a 20-year-old man and a 30-year-old man, both from the Liverpool area, were expected to appear at Inverness Sheriff Court.
The investigation earlier resulted in £180,000 worth of heroin and cocaine being recovered in Elgin and Inverness.
The operation involved Merseyside Police and officers from Police Scotland who said Thursday's activity involved the searches of several addresses in the Inverness and Liverpool areas.
Det Insp William Nimmo, of Police Scotland, said: "This recent activity serves as another example of our commitment to tackle the supply of drugs to the Highlands and Islands and to target those we suspect to be involved in the supply chain.
"This hopefully communicates a clear message that whoever you are and wherever you are from, we will continue to pro-actively target anyone suspected of being involved in the supply of controlled drugs into the Highlands."
Two men have been arrested and £50,000 worth of illegal drugs recovered as part of a probe into organised criminals from the north of England.