Iran’s supreme leader Ayatollah Ali Khamenei said on Friday that authorities would “not back down” against ongoing protests. He blamed the United States for stirring unrest. The protests began 13 days ago over economic problems but now demand political reforms. Khamenei called protesters “vandals” and “saboteurs,” accusing them of serving foreign goals. He said, “They’re ruining their own streets to make the president of another country happy … because he said he would come to their aid,” referring to US President Donald Trump. Trump warned that Khamenei might try to escape Iran soon, calling the situation “very bad.” The head of Iran’s judiciary, Gholamhossein Mohseni Ejei, promised a “decisive, maximum and without any legal leniency” response to protesters. Protest crowds grew despite a nationwide internet blackout and more police violence. Videos showed thousands marching in Tehran, burning a state TV building, and raising the old pre-1979 flag of Iran. Reza Pahlavi, son of Iran’s late shah and now exiled, urged people to protest. Supporters chanted his name even in Khamenei’s hometown of Mashhad. The protests have spread across all of Iran’s provinces in the biggest challenge to the regime in years. At least 42 people have died and over 2,270 detained, according to a human rights group. Iranian state media first acknowledged the protests on Friday, calling them violent riots by “terrorist agents” from the US and Israel. The government also claimed it caught Israeli Mossad spies involved. Internet services were cut starting Thursday night, coinciding with Pahlavi’s protest call. This made it hard to verify events or protest size. Despite police violence, protesters used rocks against security forces, forcing some to flee. Many mourned and expressed fierce anger toward the ruling clerics. A young Tehran student said, “We will burn their vans, the same that they use to drag our compatriots and kidnap our sisters from the streets. The country belongs to us!” The protests continue, with another mass rally planned by Pahlavi on Friday night at 8pm. Officials warned that the crackdown will grow harsher. The situation remains tense as Iran faces its largest wave of protests in years.