Pollka.

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To war with polka music? Who would have thought it!

From "WAR HISTORY ONLINE" the guest article by Jesse Beckett.

"The Finnish Stopped Soviet Mines from Exploding by playing a Single Polka Song on Repeat"

Vyborg mines as referred to but hardly confined to Vyborg. Vyborg a provincial city in the aftermath of the Russian Revolutionary War an integral part of the Republic of Finland approximately eighty-five kilometers [fifty miles] northwest of the 1939 border between Finland and the Soviet Union.  

"After the Finns wrestled the city of Vyborg back from the Soviets in the Continuation War (1941-1944), the Soviets, while retreating, scattered the area with mines and explosives. These mines claimed many Finnish lives"

MILITARY AND CIVILIAN BOTH!

"With the Soviets gone, the mines continued detonating, causing great confusion among the Finns as to how they were being set off . . . However, on August 28 1941 the Finns discovered 600 kgs [thirteen hundred pounds] of explosives and its triggering device. It was quickly realized that the mines were being triggered by radio signals." 

MINES PRE-POSITIONED AND DETONATED REMOTELY VIA RADIO CONTROL SIGNALS.

"A REO Speedwagon broadcast car was brought to the city and started playing the fast-paced Säkkijärven Polkka by Viljo Vesterinen . . . Over and over, the song was played in a desperate bid to block Soviet signals."

SOLUTION TO JAM THE RADIO CONTROL TRANSMISSIONS. SUCCESSFUL! POLKA MUSIC!

"The plan worked too: the city contained around 1,000 mines, but only 12 were successfully detonated."

THE SOVIET DURING THE SECOND WORLD WAR EVEN WHILE RED ARMY TROOPS ADVANCING NOTED FOR MAKING EXTENSIVE PREPARATIONS TO CONSOLIDATE CONTROL OF TERRITORY AND PREPARE FOR POSSIBLE COUNTER-ATTACK. AS WAS PRESUMABLY THE CASE IN VYBORG!

coolbert.