Anti-government demonstrations continued for a fifth day in Iran on Monday, after 10 people were killed during the biggest protests since the pro-reform unrest of 2009.
Video posted on social media showed crowds of people, some chanting 'Death to the dictator!', walking through the streets. Reuters was not immediately able to verify the footage. The Fars news agency reported on 'scattered groups' of protesters in the capital Tehran and said a ringleader was arrested.
The continuation of protests poses a challenge for clerical leaders as well as President Hassan Rouhani who appeared on TV on Sunday to call for calm, saying Iranians had the right to criticise authorities but must not cause unrest.
'The government will show no tolerance for those who damage public property, violate public order and create unrest in society,' Rouhani said. Hundreds of people have been arrested, according to officials and social media sites.
Unsigned statements on social media urged Iranians to demonstrate again in Tehran and 50 other towns and cities.
State TV said armed demonstrators had tried and failed to seize police and military bases. The intelligence ministry said 'rioters and agitators of public-unrest' had been arrested, ISNA news agency reported.
'Some armed protesters tried to take control of some police stations and military bases but they met strong resistance from security forces,' state TV said. It gave no further details and there was no independent confirmation.
State television said 10 people were killed in several cities on Sunday night and showed footage of damage to property. It did not elaborate.
Police in Tehran fired water cannon on Sunday to disperse demonstrators, according to pictures on social media.
Frustrations over economic hardships and alleged corruption erupted in Iran's second city of Mashhad on Thursday and escalated into calls for the religious establishment in power since the 1979 revolution to step down.
Some of the anger was directed at Ayatollah Ali Khamenei, breaking a taboo surrounding the man who has been supreme leader of Iran since 1989.
In the western city of Kermanshah Iranians chanted 'Death to Khamenei!' and 'If you fight, we will fight!'.
Iran is a major OPEC oil producer and regional power but frustrations have grown at home - where youth unemployment reached 28.8 percent last year - while the country is deeply involved in Syria and Iraq as part of a battle for influence with rival Saudi Arabia.
Those foreign interventions are resented by many Iranians who want their leaders to create jobs instead of engaging in costly proxy wars.
Two people were shot dead in the southwestern town of Izeh on Sunday and several others were injured, ILNA news agency quoted a member of parliament as saying. It was not clear if the two dead were among the 10 cited on state television.
'I do not know whether yesterday's shooting was done by rally participants or the police and this issue is being investigated,' Hedayatollah Khademi was quoted as saying.
Regional governor Mostafa Samali told Fars that just one person had been killed in an incident unrelated to the protests, and the suspected shooter had been arrested.
Demonstrations turned violent in Shahin Shahr in central Iran. Videos showed protesters attacking the police, turning over a car and setting it on fire. Reuters could not immediately verify the authenticity of the footage.
There were also reports of unrest in the western cities of Sanandaj and Kermanshah as well as Chabahar in the southeast and Ilam in the southwest.
The government said it would temporarily restrict access to the Telegram messaging app and Instagram. There were also reports that mobile access to the internet was being blocked in some areas.
The protests were the biggest since unrest in 2009 that followed the disputed re-election of then-President Mahmoud Ahmadinejad, and Iran's adversaries voiced their support for the resurgence of anti-government sentiment.
US President Donald Trump tweeted: 'The great Iranian people have been repressed for many years. They are hungry for food & for freedom. Along with human rights, the wealth of Iran is being looted. TIME FOR CHANGE!'
Israeli Prime Minister Benjamin Netanyahu praised the 'brave Iranians' taking to streets to protest at a regime that 'wastes tens of billions of dollars spreading hate'.
'I wish the Iranian people success in their noble quest for freedom,' he said in a video posted on his Facebook page.
German Foreign Minister Sigmar Gabriel urged 'all sides (to) refrain from violent actions'.