Kautilya's Arthashastra 7.6.41

7.6.41

ekatra tyāgaghātau ca kūṭayuddhasya mātṛkā //
yogagūḍhopajāpārthaṃ tūṣṇīṃyuddhasya lakṣaṇam //E

and bribing a portion of the army and destroying another portion, are forms of treacherous fight; and attempt to win over the chief officers of the enemy by intrigue, is the characteristic of silent battle.