Denmark’s Foreign Ministry has summoned the U.S. Envoy to Copenhagen after a report by public broadcaster DR alleged that at least three Americans with links to President Donald J. Trump are engaged in active influence operations in Greenland. Citing interviews with eight sources in Denmark, Greenland, and the United States, the investigation claims the men are working to “infiltrate Greenlandic society.” One is said to have compiled a list of Trump supporters on the island with the aim of recruiting them to form a secessionist movement against Denmark, while the other two have reportedly reached out to politicians, business leaders, and local citizens. Danish authorities fear the effort could be part of a broader attempt to advance Trump’s long-discussed ambition of annexing Greenland.