Mishra was taken to the RML hospital from his residence in Civil Lines, where he has been on a hunger strike for the last five days, demanding that the Aam Aadmi Party release details of foreign tours undertaken by five leaders.
The former Water Resources and Tourism Minister in the Kejriwal government, before taking ill, alleged that the party received funds wroth "crores of rupees" from several "shell" companies.
"All this happened with the knowledge of Arvind Kejriwal as these shell companies deposited money in the AAP bank account on the same day and time in January 2014," Mishra said, brandishing documents.
He demanded Kejriwal's resignation, and immediately after that lost consciousness.
The ex-minister had, after he was sacked, levelled personal allegations of "corruption" against Kejriwal and his minister Satyendar Jain.