A person's finger is posed next to the WhatsApp logo on an iPhone on Aug. 3 in London. Getty Images

Hundreds of people were recently taken into custody in Iran for using social media messaging services like WhatsApp, Telegram and Instagram. The Revolutionary Guards' Gerdab site reported Tuesday that "the managers of 450 pages, channels and social networks" were "invited, summoned or arrested" by authorities for their internet habits.

"These people were carrying out immoral activities, insulted religious beliefs or had illegal activities in the field of fashion," the Gerdab wrote, according to a translation by the Al-Monitor. Vocativ reported that investigators learned about the suspects from their followers.

Technology Prevalence in Iran Over Time | FindTheData

Social media censorship is common in Iran, where, as of 2012, a quarter of all websites were blocked, among them Facebook, Goodreads, MapQuest, Rotten Tomatoes, NBC, PBS and Nickelodeon, according to TheNextWeb. More than 67 percent of Iranian youth use the internet freely anyway, with about the same proportion setting up virtual private networks to go around the filters, TechRasa reported.

The app-related arrests revealed this week weren't the first time officials have cracked down on internet use.

Though President Hassan Rouhani supports unblocking social media, a council under Supreme Leader of Iran Ayatollah Ali Khamenei ordered earlier this year that all foreign apps turn over "all data and activity linked to Iranian citizens ... in order to ensure their continued activity," Reuters reported. In May, at least eight people were arrested for not wearing their headscarves in Instagram photos, Al Jazeera reported.

According to a Tuesday article from the National Council of Resistance of Iran, young people — between 19 and 27 years old — have been particularly affected by the crackdown on "internet crimes" recently.

"Before, people have been arrested and sentenced for posting material on social media that was deemed offensive to government officials, or were seen as a threat to national security," Human Rights Watch researcher Tara Sepehri Far told BuzzFeed in May. "But over last year or so, the debate in Iran has shifted towards the influence of lifestyle, and the government is deciding how people who do not conform to the desired lifestyle should be treated."