A crackdown on nationwide protests in Iran has killed at least 544 people and even more are feared dead, activists said Sunday, while Tehran warned that the U.S. military and Israel would be “legitimate targets” if America uses force to protect demonstrators.

Some 544 people have died so far in nationwide protests in Iran, according to activists, as demonstrations hit the three-week mark and have turned into one of the most serious challenges to the regime in Tehran in recent years.

Iran's parliament speaker warns that the U.S. military and Israel could be 'legitimate targets,' possibly in a preemptive attack, if the U.S. strikes Iran over ongoing protests.

Violence surrounding the nationwide protests now shaking Iran has killed at least 203 people, with fears the death toll is actually far

A crackdown on nationwide protests in Iran has killed at least 538 people and even more are feared dead, activists said Sunday, while Tehran warned that the U.S. military and Israel would be

Meanwhile, Tehran warned that the U.S. military and Israel would be “legitimate targets” if America uses force to protect demonstrators.

Iran’s parliament speaker warns the U.S. military and Israel could be “legitimate targets” if the U.S. strikes Iran over ongoing protests.

It remains unclear just how serious Iran is about launching a strike, particularly after its air defenses were destroyed during the 12-day war in June with Israel.