Nine people, were killed in overnight clashes between anti-government protesters and police in Iran between Monday and Tuesday, the state television reported.

Since the demonstrations started on Thursday, the death toll reached 20.

Protests took place in Mashid, over high prices.

The rallies later on expanded to several cities in Iran.

Hundreds of people were detained over the unrest, including 450 arrested in Tehran, ILNA news agency reported.

According to state TV, an 11-year-old and a 20-year-old were killed in the town of Khomeinishahr.

A member of the paramilitary Revolutionary Guard was also reported killed.

A policeman was killed while three other officers were injured during a protest on Monday, according to Mehr news agency.

The U.S condemned the arrests made by Iranian security forces after thousands of Iranians took to the streets in protests.

US President Donald Trump,urged nations to support the Iranian people, which angered the Iranian government, leading the Foreign Ministry spokesman to say: “Iranian people give no credit to the deceitful and opportunist remarks of U.S. officials or Mr. Trump”.

Meanwhile, Iran's President Hassan Rouhani, warned that rioters will be arrested.