The […] 48th Panzer Corps tried to launch a counterattack. They met the attacking Soviet forces head‐on near the village of Ust‐Medveditsky. An enormous tank battle raged for more than a day. At its end, the […] Panzer Corps lay crushed. Ones of its divisions had been hindered by an unlikely foe. While the division had been in reserve with its vehicles standing idle, field mice had got inside the vehicles and gnawed through the electrical wiring. This humble ally of the Red Army had put dozens of tanks out of action.

(Emphasis added. Source herein.)