Shiva Purana
इत्युक्त्वा हुंकृतेनैव भस्मसात्कृतवांस्तदा॥ दूषणं च महाकालः शंकरस्सबलं द्रुतम् ॥ ३९ ॥
After saying this Śiva reduced Dūṣaṇa and his army, to ashes immediately with a mere sound of Hum.
english translation
ityuktvA huMkRtenaiva bhasmasAtkRtavAMstadA॥ dUSaNaM ca mahAkAlaH zaMkarassabalaM drutam ॥ 39 ॥
hk transliteration by Sanscript