"Today, we can say it is the end of 'sedition 1396,' " Jafari said, using the year in the Iranian calendar.
"With the help of God, their defeat is definite," he said.
Jafari offered no evidence of how the movement had been defeated beyond the arrests, and his comments appeared to be a warning against more rallies.
The protests began last Thursday over Iran's stagnant economy and the rising cost of living but quickly have developed into a broader outcry against the government.
They have become the most powerful challenge to the Iranian government's authority since mass demonstrations in 2009.
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