Choudhary, mayor of the South Municipal Corporation, was considered a strong contender for a BJP ticket from the Mehrauli constituency. The BJP decided to field Parvesh Verma from there. Disgruntled party workers said the man was an "outsider".
Verma, son of former Delhi chief minister Saheb Singh Verma, was expected to contest from Mundka, once the bastion of his father.
Harshvardhan tried to calm the mob but to no avail
Waving black flags, party workers stormed the conference room in the party office, just as a press conference held there concluded. State party chief Vijay Goel, Vijender Gupta and senior leader V.K. Malhotra fled the scene as the party's Delhi chief ministerial candidate Harsh Vardhan was heckled.
Harsh Vardhan attempted to calm down the irate mob, but his words failed to have any effect, and he was escorted out by security guards.
The party Wednesday declared the list of candidates for 62 seats, of which four will be contested by its old ally, Shiromani Akali Dal.