Riot police clashed with protesters in Tehran yesterday amid growing signs of panic at Iran’s collapsing currency as pressure from international sanctions sent the rial plunging to record lows this week.

Police fired teargas at stone-throwing demonstrators after traders in the main bazaar closed their shops and staged a protest demanding government action to halt economic meltdown. Another protest by about 200 people was also broken up outside Iran’s central bank. Witnesses said that dozens were arrested.

The scale of public anger, and the regime’s draconian response, suggested that Iran could be on the verge of its worst civil unrest since the protests that followed the disputed 2009 presidential election, prompting a government crackdown that left hundreds dead.

Yesterday protesters chanted: “Leave Syria alone and