In 2015, Mishra had led a signature campaign by a number of AAP MLAs to sack Mr Yadav and Mr Bhushan for "anti-party activities".
The two leaders had questioned Mr Kejriwal's style of functioning and were later sacked from the party.
"I have realised the wrongdoings in the party now. Many people realised these things before and left. But we have to ensure that the party is not left to some corrupt people," Mr Mishra told reporters.
Yongendra Yadav, who along with Prashant Bhushan later formed another political outfit Swaraj India, demanded that Kapil Mishra apologise to the party volunteers.
"Nothing personal, @KapilMishraAAP Apology due to all volunteers. Best to put all facts about that episode in public," Mr Yadav tweeted.
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