TEHRAN, Iran (CNN)  -- A defiant and chaotic protest sprouted in and around a public square Monday despite a warning by Iran's Revolutionary Guard against the kind of street demonstrations that have roiled Iran for more than a week, witnesses said. Security forces patrol the streets of Tehran on Monday. Thousands of Iranians congregated and passed through Haft-e Tir Square, but riot police and the pro-government Basij militia confronted them and smacked their batons against their shin guards, making loud cracking sounds that seemed like gunshots, the witnesses said. As the protests continued, an election official with the Interior Ministry said the "box-by-box details" of the ballots -- which were confidential in previous elections -- would be released in response to claims that the election was rigged, Press TV reported.
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NEW: Interior Ministry will release box-by-box ballot details, Press TV reports
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Basij militia smack batons against shin guards as protesters pass through square
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Helicopters hover as thousands play cat and mouse with police, witnesses say
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At least 8 reported arrested, but no reports of serious injuries
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