As protests continue over the death of a woman in police custody in Iran, access to Instagram and WhatsApp has been blocked.

Meanwhile, there have been major internet outages across the country, with cellphone services also disrupted.

Last week, 22-year-old Mahsa Amini died after being arrested by the country’s morality police for ‘unsuitable attire’ – a hijab she was perceived to be wearing improperly. The authorities deny any wrong-doing, claiming she suffered sudden heart failure. Since then, however, there has been a wave of protests across the country, with at least eight people reported to have been killed.

Now, according to data from NetBlocks, the authorities have hit back with a series of internet restrictions – the most severe, says the firm, since the November 2019 massacre that left more than 300 dead.

Twitter and Facebook have long been banned in Iran. However, Instagram and WhatsApp have now been restricted for all users registered with an Iranian, +98, phone number, across all major network operators. Meanwhile, mobile networks, including MCI, Rightel and Irancell, have been largely shut down.

“Users have also reported the disconnection or severe slowing of internet service in multiple cities since the first disruption was registered on Friday 16 September 2022,” says NetBlocks.

“The network disruptions are likely to severely limit the public’s ability to express political discontent and communicate freely.”

Because traffic has been disrupted at the network layer, it’s not generally possible to bypass the block by using circumvention software or virtual private networks (VPNs).

Iran is one of the world’s worst offenders when it comes to intenet shutdowns, blocking internet access at least five times during 2021.

In a joint statement, groups including Access Now, PEN America and Reporters Without Borders are calling on the International Telecommunication Union (ITU) to demand that Iran reverse its moves.

“We also call on the Iranian government to enact policies, practices, and legislation in line with international human rights law that recognizes the fundamental role that the internet plays in the exercise of human rights, and guards against shutdowns,” they write.

“In the past, the Iranian government has demonstrated a similar pattern of preferential treatment and tiered access, in which institutions including banks, news agencies, police stations, and government offices have remained connected to the internet, while regular people in Iran, who use the same ISPs, have been disconnected. Authorities must do everything in their power to ensure internet access for all in Iran.”

The shutdowns come as pro-government websites suffer outages of their own. Hactivist group Anonymous says it’s carried out attacks against two government websites and the Iranian state television channel, along with other sites.

“The Iranian people are not alone. Anonymous will not keep the Iranian government alive on the internet as long as they fight the dictatorial rule and murderous cops,” it says in a video statement.

“You censored your people’s social media and other communications to suppress knowledge of your crimes against them. Now Anonymous will shut you down, and your own people will remove you from power.”