Dozens of supporters, carrying yellow umbrellas which have become a symbol of the movement and shouting "I want true democracy without fear!", surrounded the trio as they turned themselves in at a central police station.
However Benny Tai, Chan Kin-man and Chu Yiu-ming quickly emerged from the station, saying they had not been arrested despite admitting "participating in unauthorised assembly".
"We have not been arrested so we are allowed to leave with no restriction on our liberty," said Tai.
"I don't think the matter will be resolved on this occasion, later we may be arrested, even prosecuted for more serious offences," Tai added.
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The three had been joined by 82-year-old Cardinal Joseph Zen, a prominent pro-democracy supporter, who also gave himself up.
About 40 other supporters waiting outside the police station also queued up to fill out forms turning themselves in.
"This is for the fortune of the next generation," said secondary school teacher April Fan, 55.
"They were explicitly told by the interviewing officers that illegal occupation of public places was an unlawful act and they should stop such act immediately," a statement said.
"Police will conduct follow-up investigations based on the information provided."
While there was no warrant for the founders' arrest, Hong Kong and Chinese authorities have consistently slammed the protests as illegal.
The founders' "surrender" and their call to end the road blockades followed violent clashes between protesters and police outside the government headquarters late Sunday which left dozens injured.
Tai said the Occupy movement would now take a different approach to promoting democracy, including through education and a new social charter.