कोटीजघनघातैर्वा दूतव्यञ्जनभेदनैः ॥ कZ_१०.६.४९च्द् ॥
koṭī-jaghana-ghātair vā dūta-vyañjana-bhedanaiḥ.
Or by striking the flanks and rear, and by breaking (compromising) the messenger-system and its signals/codes.
Compromising communications: intercepting couriers, forging messages, breaking codes, and disrupting signaling to paralyze command.
Physical dislocation plus informational paralysis prevents regrouping and accelerates rout.