President Hassan Rouhani acknowledged public concern about the economy but warned lawbreakers would be punished. At least 36 people were killed in 2009, according to an official toll, while the opposition says 72 died.
It was unclear if this was the same fatality as that reported by Iran's semi-official Mehr news agency on Monday. Protesters have complained mostly about economic problems and have also denounced Iran's clerical leadership.
The towns are all in Iran's central Isfahan province, about 215 miles south of Tehran.
The protests are widely described as the largest since 2009, when demonstrators took to the streets to following the disputed re-election of President Mahmoud Ahmadinejad.
"At the moment, the protests do not constitute a threat to the survival of the regime, but they do weaken it and undermine its legitimacy, and they are likely to threaten its stability in the long term", it reportedly states.
Deputy Chief of Staff and Spokesman of Iran's Armed Forces Brigadier General Massoud Jazzayeri lashed out at US President Donald Trump for his support for protests in Iran, warning of Washington's new plots.
Separately, and following reports about the suspension of the internet service in several cities, the Amad News channel, which played a leading role in mobilizing the people to protest in the streets, said the USA may launch a satellite that provides free services for internet users in Iran.More news: 12 dead, several injured in Bronx building fire
Police used tear gas and water cannons to disperse a small protest in Tehran's Enghelab Square on Sunday evening, according to unverified social media videos.
The protests began Thursday in Mashhad, Iran's second-largest city, and quickly spread across the nation, with some protesters chanting against the government and the supreme leader, Ayatollah Ali Khamenei. They are hungry for food and for freedom.
Police arrested a number of demonstrators who were trying to damage public property in the gatherings. Along with human rights, the wealth of Iran is being looted.
Previously, Germany called on both Iranian authorities and the protesters to restrain from violence.
In a statement on Twitter, the ministry cautioned that Iran was seeing "large-scale disturbances and an unstable security situation" as well as "grave acts of violence". But there's only ONE way to change Iran: from inside, by the Iranian people.
Bahrain's Shiite community generally travels to Iran for religious reasons, although relations between the countries are strained over allegations by Manama that Tehran interferes in its internal affairs.