An Iranian Judiciary official on Thursday said 135 young men and women "whose appearance resembled devil worshipers" were arrested in the suburbs of the capital Tehran.
Iranian authorities consider certain types of clothing, paraphernalia and accessories such as those with Gothic symbols as well as body art and rap, rock, and Metallica music as signs of "Satanism".
According to the Prosecutor of Damavand city west of Tehran, "the 135 girls and boys" who were arrested at a party in an industrial shed wore "devil worship symbols".
The youth were in possession of mind-altering drugs, knives, and sabres and "committed other illegal activities such as bearing tattoos", he said and added that some of them are in detention and others have been freed after providing the required guarantees.
Damavand is a county an hour away from the capital where well-to-do Tehranis often hold parties away from the eagle eyes of the morality police, in secluded opulent villas dispersed around the mountains and hills. Those who are not lucky enough to have villas often opt for abandoned industrial sheds and fruit orchards.
Mixed parties with music, dance and alcohol are often raided by the morality police and participants are arrested but sometimes the expectation of being raided adds to the thrill of the party.
Hardliners who allege western music is a tool in the "cultural onslaught of the West" against the Islamic Republic, consider heavy metal as the most dangerous type of underground music and closely associate it with Satanism.
Why do authorities allow heavy metal concerts "which is even worse than drugs" to be held in universities or taught in music schools, a commentary published in a hardline news website called Dana asks.
"There are now more than 70 devil worship sects active in the country which try to destroy belief in God and afterlife in the hearts of our youth by propagating corruption, self-indulgence and blood drinking," the commentary says.
In 2008 the state-run television aired a documentary called "Shock" in which underground rap music was associated with Satanism. Underground music concerts are often held in isolated barns and industrial sheds.
The police often raid retail shops and confiscate or destroy clothes and accessory symbols they associate with Satanism and arrest individuals for selling or using them. On October 30 the police in Karaj, a city in the west of Tehran, arrested five individuals for "propagating western culture and selling clothes with Devil worship symbols".
Interestingly, some of these clothes are apparently popular with the young people participating in religious mourning ceremonies such as Ashura. According to the Police Commander of Qazvin the police had to confiscate black clothes "with Devil worship symbols and insignia" ahead of the annual Ashura procession in September this year.
In May this year the authorities arrested 10 individuals who allegedly were "leaders of a Devil worshipers' tour" in which more than 200 people had participated in the forests of Amol in the northern holiday resort areas of the country.
The hardline religious and political establishment have in the past few years claimed that social media such as Instagram and Telegram are "tools in the hands of Devil worshipers". Telegram is particularly popular in Iran where it has more than 50 million subscribers.
In April the Cyberspace Police (FATA) arrested a Telegram channel creator with more than 4000 subscribers in Babol in the north of Iran on various charges including "spreading corruption and devil worship".