"What happened at the AAP meeting in Delhi today is unfortunate," Patkar told reporters in Mumbai after announcing she was leaving the party, which notched up an unprecedented victory in Delhi Assembly polls just last month.
"Political principles are being trampled upon in the party," said the veteran activist, who has been a key figure in the Arvind Kejriwal-led outfit.
"I condemn what happened with Prashant Bhushan and Yogendra Yadav," Patkar said, adding AAP has become a 'tamasha'.
Earlier in the day, Bhushan and Yadav were removed from AAP's National Executive for anti-party activities, a decision slammed as "murder of democracy" by them.
Amid chaos and high drama, a resolution to remove the two dissident leaders along with their supporters Anand Kumar and Ajit Jha from the powerful panel was passed at a National Council meeting.
Announcing her decision to quit the party at a media conference at her office in Mumbai, Patkar said, "We have seen such kind of drama in other political parties, but didn't expect this in AAP.
"Prashant Bhushan, Yogendra Yadav and Anand Kumar are people who contributed to the image and manifesto of the party. I don't know if they ever acted against the party."
"I was expecting that there will be a solution and, if somebody is making a critical remark, there will be a decision only after discussion. But the image that has come in front of us, we condemn that. Dirty linen must not be washed in public," she added.
Patkar said that Bhushan and Yadav were among those who had contributed to the party and claimed that they were not part of any lobby or group and the charges against them were false.
She said there were no complaints about Arvind Kejriwal and his team and people had given him the mandate and "he should continue his work".
As to her resignation, Patkar said, "I took the opinion of conveners in all the states... I never took any position in AAP because I sensed something was not good. So, I quit the party."
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