Mehndi and four others had applied for party membership and their requests have been accepted, said a source in the party's Delhi unit.
The four others include two sitting Delhi legislators - Ram Singh of the Bahujan Samaj Party and Asif Mohammad Khan, who is an Independent.
The two others are Ram Singh Bidhuri, a former Nationalist Congress Party (NCP) legislator, and V.K. Monga.
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