Kautilya's Arthashastra 13.4.26

13.4.26

svayam agnau jāte samutthāpite vā prahavaṇe prekṣānīkadarśanasaṅgasaurikakalaheṣu nityayuddhaśrāntabale bahulayuddhapratividdhapretapuruṣe jāgaraṇaklāntasuptajane durdine nadīvege vā nīhārasamplave vāvamṛdnīyāt //

When fire, accidental or intentionally kindled, breaks out; when the enemy's people are engaged in a sacrificial performance, or in witnessing spectacles or the troops, or in a quarrel due to the drinking of liquor; or when the enemy's army is too much tired by daily engagements in battles and is reduced in strength in consequence of the slaughter of a number of its men in a number of battles; when the enemy's people wearied from sleeplessness have fallen asleep; or on the occasion of a cloudy day, of floods, or of a thick fog or snow, general assault should be made.