Amnesty International says Iranian security forces have killed at least 106 people in nationwide anti-government protests since Friday, four times the death toll of Iran's last mass protests two years ago.

In a Tuesday interview with VOA Persian, the London-based rights group's Iran researcher, Raha Bahreini, said Amnesty determined that security forces killed 106 protesters based on eyewitness accounts, social media videos and reports of exiled Iranian human rights activists.

An Amnesty press release said it recorded fatalities of protesters in 21 towns and cities, with the highest numbers of deaths occurring in five western cities: Kermanshah, Javanroud, Bandar-e Mahshahr and its suburbs, Mariwan and Behbahan.

VOA Persian has independently confirmed the killings of at least seven protesters in shootings by Iranian security forces on Saturday.

Iranian state media have said several people were killed, including at least one security force member in the demonstrations that began Friday and spread to dozens of cities. But the Iranian government has not released any official numbers on deaths and injuries or arrests of protesters.

Iranian state TV broadcast images of pro-government rallies in several locations on Tuesday, in an effort to minimize the protests. Authorities also extended an almost complete shutdown of internet access into a fourth day to stop Iranians from sharing images of the protests with the outside world. The outage, which began late Saturday, made it difficult to determine the extent of Tuesday's protests.

The demonstrations erupted in response to the government abruptly raising the subsidized price of gas by 50 percent early Friday. Many Iranians see the increase as putting a further burden on their wallets at a time of worsening economic conditions.

Bahreini said Amnesty has called on the United Nations and European Union to make urgent appeals to Iran to end its violent crackdown on the protests and to respect Iranians’ rights to freedoms of expression and assembly.

Iran violently suppressed the last major wave of nationwide protests that swept the country from late December 2017 to early January 2018. At least 22 people were killed in the crackdown on those protests, which were fueled by public anger with government corruption and mismanagement.