Srimad Bhagavatam Canto 07, Chapter 07, Text 02

SB 7.7.2

sri-prahrada uvaca
pitari prasthite ’smakam
 tapase mandaracalam
yuddhodyamam param cakrur
 vibudha danavan prati
 
Translation by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada: 
 
Prahlada Maharaja said: When our father, Hiranyakasipu, went to Mandaracala Mountain to execute severe austerities, in his absence the demigods, headed by King Indra, made a severe attempt to subdue all the demons in warfare.
Srimad Bhagavatam Canto 07, Chapter 07, Text 01
Srimad Bhagavatam Canto 07, Chapter 07, Text 03