Traders from Isfahan, Kermanshah, and Arak joined the protesters Tehran on Tuesday by closing their stores.
Iranian officials blamed foreign enemies and some traders who want to benefit from high inflation.
"Today the enemy hopes that by psychological attempts in the economic conditions to create chaos in the country," Sadegh Larijani, the Iranian minster of justice, told Tasnim news agency on Tuesday.
Thousands of traders from Tehran's Grand Bazaar took to the streets on Monday protesting against the increasing devaluation of Iranian currency.
Riot police can be seen deploying in Iran's capital of Tehran on June 26, 2018. Video: Amadnews
They aimed to walk from the market to parliament, but riot police responded with tear gas, according to videos published on Telegram channels.
"Death to the dictator" and "Leave Syria, Care about us," cried the protesters.
The USD equaled 80,000 rials on Sunday. On Wednesday, the dollar traded at about 100,000 rials, but the official government rate is just 42,000.
The result of the rial's falling value is an increase of the price for imports because the US dollar is the dominate currency for foreign trade.
On May 9, US President Donald Trump withdrew from the Iran nuclear deal, sending shock waves through the Iranian economy.
In the last six months, Iran's currency has lost more than 50 percent of its value. Iranians have reacted by trying to invest in dollars and gold. The demand for dollar has increased considerably as the Iranian people rush to exchange the local currency to dollar and gold coins that have more stable values.
In December 2017, Iranians mostly from outlying areas protested across the country demanding better living conditions; however, this round of protests has struck in major cities.
