Srimad Bhagavatam Canto 05, Chapter 26, Text 21

SB 5.26.21

yas tv iha vai sarvabhigamas tam amutra niraye vartamanam vajrakantaka-salmalim aropya niskarsanti.
 
Translation by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada: 
 
A person who indulges in sex indiscriminately — even with animals — is taken after death to the hell known as Vajrakantaka-salmali. In this hell there is a silk-cotton tree full of thorns as strong as thunderbolts. The agents of Yamaraja hang the sinful man on that tree and pull him down forcibly so that the thorns very severely tear his body.
 
Purport by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada: 
 
The sexual urge is so strong that sometimes a man indulges in sexual relations with a cow, or a woman indulges in sexual relations with a dog. Such men and women are put into the hell known as Vajrakantaka-salmali. The Krsna consciousness movement forbids illicit sex. From the description of these verses, we can understand what an extremely sinful act illicit sex is. Sometimes people disbelieve these descriptions of hell, but whether one believes or not, everything must be carried out by the laws of nature, which no one can avoid.
Srimad Bhagavatam Canto 05, Chapter 26, Text 20
Srimad Bhagavatam Canto 05, Chapter 26, Text 22