Dresden, 5 December 1989: the mob, the furnace, the bluff
"They are burning the secret files so fast that the furnace is blowing up."
The core is documented. Demonstrators stormed the Stasi district headquarters that evening, then moved on the KGB villa nearby on Angelikastraße, and Putin went out to confront them. Files were destroyed.
The dramatic detail is not independently documented. It traces to Putin's own 2000 interview book First Person and later Russian television retellings, in which, as German reporting notes, hundreds of demonstrators became "thousands" and Putin became a hero. The exploding furnace, the count of thousands of pages, and the exact wording of the threat are his account of himself. Treat the scene as substantially true and theatrically inflated.