Traitors with Andrey Lugovoi – Tolkachev
Intelligence can use both legitimate methods of collecting information (for example, collecting and analyzing open-source data, eavesdropping on foreign radio channels, and surveillance using reconnaissance satellites) and illegal operations, falling under the definition of "espionage" or "information theft."
"In recent years, the capabilities of intelligence disciplines such as radio and electronic intelligence, imagery, and special technical intelligence have expanded, primarily due to the spread of information technology. But the real breakthrough was achieved through the integration of these intelligence disciplines, as well as the coordination and cooperation of all intelligence elements."