Two people were killed overnight in the western province of Lorestan amid anti-government protests erupting across the country, the province's deputy government confirmed Sunday while denying reports of security forces opening fire on demonstrators.

Habibollah Khojastehpour told reporters that the two citizens were killed Saturday in an illegal gathering in the city of Dorud that turned violent.

"No shots were fired by the police and security forces in Saturday's rallies. Officials were trying to end the gathering peacefully," he said.

He added that "the footprint of Takfiri groups and foreign (intelligence) services are completely obvious in this story," using a term referring to Sunni militants.

However, BBC Persian and Reuters, based on video circulating on social media, reported that the two were shot dead by security forces. The videos showed two young men lying motionless and covered with blood on the ground, with a voice overheard saying they had been shot dead by the police.

Since Thursday, hundreds of people in various cities across the country have taken part in protests against inflation, alleged corruption by officials and economic policies of the government.

The protests began in Mashhad, Iran's second-largest city, which is a base for hardliners who basically oppose the policies of pragmatist President Hassan Rouhani.

A day after rally in Mashhad, at which the crowd chanted "Death to Rouhani," First Vice President Eshaq Jahangiri accused hardline rivals of being behind the demonstrations. "The fire which they had set will burn their own fingers," Jahangiri said.

On Friday and Saturday, the protests spread to other cities including the capital Tehran, Qom, Kermanshah, Dorud, Rasht, Arak, Ahwaz and Zanjan, becoming increasing violent along the way.

Although Iranian officials in the last three days tried to calm down the protesters in a peaceful way, more than 150 protesters are reported to have been arrested by security forces in Tehran, Mashhad and Arak.

On Saturday, students at Tehran University also joined the protests, chanting slogans against the Islamic Republic's policies in front of the university. Some videos posted on social media showed tear gas being fired into the students.

Later in the evening, the protesters damaged public transportation and bus stations in central Tehran while others in Mashhad set fire to police motorcycles and others damaged banks and state-owned buildings in Ahwaz.

Interior Minister Abdolrahman Rahmani Fazli on Sunday said that the government and parliament are following the request of the people and trying to resolve the problems.

"The authorities will definitely punish those who are trying to spread fear in society by violating and breaching the law," the ministry's official website quoted Fazli as saying.

He added that those who damage public property, disrupt order and break the law "must be responsible for their behavior and pay the price."

In parts of the capital Tehran on Sunday, mobile phones could not access the internet, indicating that the security authorities were tightening information controls.

Anti-government demonstrations are rare in Iran as they are usually suppressed by security forces.

The current protests to be the most serious since unrest in 2009 following the presidential election. The authorities are blaming the unrest on anti-revolutionaries and agents of foreign powers.