Iran’s Supreme Leader Ayatollah Ali Khamenei said on Sunday that anti-government protests that took place in January amounted to an attempted “coup,” adding that the effort had failed.

Khamenei was quoted by Iran’s Tasnim news agency as saying that protesters “attacked police, government buildings, Revolutionary Guards barracks, banks and mosques, and burned copies of the Quran.”

In separate remarks, Khamenei warned that any U.S. attack on Iran would trigger a regional war, amid a significant U.S. military presence in the region and threats by President Donald Trump against the Islamic Republic.

“Americans should know that if they start a war, it will be a regional war,” Khamenei said, according to Tasnim.