Sandeep Kumar, the Aam Aadmi Party (AAP) leader said in a statement, had "betrayed" the AAP movement and all those who had quit their jobs to be a part of it.
"Sandeep Kumar has betrayed the entire movement. AAP is the sole hope of the entire country. He had betrayed their hope," Kejriwal said.
The Chief Minister ordered Sandeep Kumar's sacking on Wednesday night after coming in possession of a video which showed the minister with a woman in an "objectionable position".
Sandeep Kumar on Thursday claimed innocence, saying he was targeted because he was a Dalit.
Kejriwal said it was but natural for people to ask at this juncture if there was any difference between the AAP and other parties.
He said if any evidence of wrongdoing was brought against any AAP leader or minister, the party immediately acted on it. This did not happen in other political parties.
Meanwhile, the BJP latched onto the issue and said the "real face of Arvind Kejriwal has now been exposed."
"There's not an even an iota of evidence of corruption against BJP CMs. Kejriwal is just playing second fiddle to Rahul Gandhi," GVL Narasimha Rao, BJP spokesperson said.