Sources said that Garg was a "serial offender", which led the party to take the decision.
Last week, Garg, a former MLA from Rohini, had accused Kejriwal of trying to poach six Congress MLAs to form a government in Delhi last year. He had also recorded a telephonic conversation between him and Kejriwal, which later surfaced and was circulated in the media. Garg said he had emailed the recording of the conversation to senior party leader Kumar Vishwas.
Kumar shot back saying Garg was trying to blackmail him as he wanted party ticket for the assembly election. Garg had also sent a legal notice to Vishwas for calling him a "blackmailer".
The decision also comes following the legal notice sent to Vishwas. It was not the first time that the former Rohini MLA was on the wrong side of the party leadership.
In October last year, he had questioned Kejriwal about the internal party democracy and also on whether he should have consulted people on conducting fresh polls in Delhi.
Garg is the second former AAP MLA to have faced disciplinary action by the party. Last year, Vinod Kumar Binny, a former AAP MLA representing Laxmi Nagar constituency, was sacked from the organisation for anti-party activity.
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