Transcript for People in Iran protest against its regime

We turn overseas tonight, and to Iran, protesters taking to the streets again tonight, nearly a week now. Clashes with authorities turning deadly. And the president tweeting until F in favor of them. Here's ABC's chief foreign correspondent Terry Moran. Reporter: Today, in Iran, streets on fire. Protesters clashing with police, banks and public buildings attacked. Some in the crowds chanting revolutionary slogans. "Down with the dictator," they cried. And now a hard line from Iran's supreme leader, who claimed enemies of Iran for bringing the unrest. While a prominent judge warned some protesters could face the death penalty. President trump has strongly supported the protesters, twe tweeting, the people of Iran are finally acting against the brutal and corrupt Iranian regime. At the U.N. Today, Nikki Haley echoing the president. We must not be silent. The people of Iran are crying out for freedom. Reporter: It's the sixth straight day of these protests. Hundreds arrested. At least 21 killed. Largest demonstrations since 2009. But back then, it was millions in the streets. Now, it's tens of thousands. Still, the world seeing images like this, a young woman in a Claude of tear gas, her clienched fist raised here. Iranians we talk to it's the economy, the nuclear deal many hoped would spur growth, and raise their incomes. It hasn't. And now, they're desperate and angry.

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