Riot police swarm Tehran bazaar amid anti-Ahmadinejad protests Iranian President Mahmoud Ahmadinejad waves during a press conference in Tehran on October 2, 2012. NEW: Protests break out in another area of the capital as well NEW: Ahmadinejad also blamed 22 Iranian "ringleaders" for manipulating currency Riot police swarm a Tehran bazaar as demonstrators lash out over the plummeting rial The Iranian president blamed Western sanctions and "psychological warfare" Tehran, Iran (CNN) -- Iranian riot police swarmed a major bazaar Wednesday in Tehran as demonstrators launched protests against firebrand President Mahmoud Ahmadinejad, blaming him for plummeting currency that's forcing families into poverty. A day after Ahmadinejad acknowledged that his country is taking a hit, and placed the blame largely on "the enemy's" sanctions, crowds of protesters also took to the streets in another commercial area in the capital, shopkeepers said. They chanted slogans slamming Ahmadinejad's regime and complained about the high prices of goods and food. Riot police dispersed the crowd, a shopkeeper said. The United States and European Union have imposed numerous sanctions aimed at pressuring Tehran into sitting down for international negotiations about its nuclear program. Earlier this week, U.S. State Department spokeswoman Victoria Nuland said the falling value of the rial comes as "firms all over the world are refusing to do business with Iranian companies." She cited "the most punishing sanctions we have ever been able to amass as an international community," calling them, "very important for trying to get Iran's attention on the important denuclearization work." At the main bazaar in central Tehran, some protesters used boxes and tires to start fires, according to a merchant who spoke on condition of anonymity for security reasons. But the semi-official Mehr news agency quoted the head of the bazaar's merchant's association as saying that officials had observed "suspicious" activity and identified people around the market who were from "outside the bazaar community." The bazaar was closed for safety reasons, Mehr reported. Dozens of police on motorcycles responded to the scene, and dozens more were on foot. Police also gathered in two major squares -- Ferdosi and Vali Asr -- although no demonstrations were immediately reported in those spots. In a speech Wednesday, Ahmadinejad also said part of the problem plaguing the country's currency is "internal." He blamed "22 ringleaders" who the country's intelligence services have determined are causing tensions and manipulating currency. The president gave no details. But people who trade currency illegally have been increasingly concerned about a crackdown by Iranian forces. Months ago, an Iranian man told CNN that with the country's economic downfall, the only way for his sons to live a decent life was to fall in with influential people or make shady business deals -- such as trading foreign currency on the black market. But Ahmadinejad focused the majority of his remarks on the United States and the West. U.S.: Iran currency woes show sanctions working "There is a hidden war, a very pervasive and heavy warfare that is happening across the world directed towards Iran," he said. Ahmadinejad insisted the sanctions hurt the people, not the government. The "enemy" has "succeeded in reducing the sale of our oil to an extent, but God willing, we will fill it up," he insisted. The country's economy "has become a tool for psychological warfare," the president said. Amadinejad tells U.N. Iran is threatened CNN's Shirzad Bozorgmehr reported from Tehran; CNN's Josh Levs reported from Atlanta. CNN's Reza Sayah also contributed to this report.