At least 115 people have been killed by Iranian security forces during protests over higher fuel prices over the past week, Amnesty International said on Saturday amid reports that the internet was gradually being restored in many parts of the country.
The human rights organization said in a tweet that its figure was based on "credible reports," and said they believed the real number to be much higher.
"We urge states to bring Iran's authorities to account," Amnesty added.
As of Friday, Tehran has said nine people were confirmed dead but no official tolls have been released since then.
Protests broke out across Iran on November 16 against an increase in the price of petrol and the rationing of fuel.
The government shut down most domestic internet access several days ago to prevent the spread of information and images of the unrest.
NetBlocks, an organization that tracks internet access, said on Saturday that internet access was gradually being reinstated.
The group tweeted that internet connectivity was at 64 per cent of normal levels.
Iran's Islamic Revolutionary Guard Corps, an elite government agency, declared the unrest to be over on Thursday.
Revolutionary Guard spokesman Ramazan Sharif said that "the leaders of the riots were identified and arrested" and there had been fewer than 100 incidents across Iran related to the hike in petrol prices.
Sharif claimed the protest leaders were financed by outsiders "who want to take revenge for the overthrow of the shah's regime," referring to pro-Western Shah Mohammad Reza Pahlavi in 1979.
