Garudapurana 1.106.18

1.106.18

nivāsarājani tathā tadahaḥ śuddhikāra(ṇa)m /
hatānāṃ nṛpagoviprairanvakṣaṃ cātmaghātinām //

and likewise for the king of one's dwelling-place, that day is the cause of purification. / Immediate [purification is ordained] for those slain by a king, a cow, or a brāhmaṇa, and for suicides;