Flight of the Silver Eagle by Arthur Leo Zagat

Atkins fumbled in his pocket with shaking fingers, pushed the paper across the desk to the chief of the Silver Eagle. The red lines on it leered at him again, the ominous design that had pronged him with knowledge of the catastrophe that had overtaken Thomas. A deftly drawn dragon was coiled around the orb of Earth, one taloned claw sprawling triumphantly to obliterate the double triangles of the Americas.

The chief’s grey face was almost expressionless as he touched the thing with a fingertip, but under his pale, inscrutable eyes little muscles twitched uncontrollably.

“The token of Hung-Chen,” he said. “Like him to let us know that he’s defeated our last device against his spies.”