Muslims No Longer Allowed to Buy/Rent Property in Indian City

Tell me, where/when did the the real estate brokers in an entire city form an association and decide that they will not sell/rent any property in that city to members of any other community? Have the realtors of Poona or Bombay ever gathered and declared that they will no longer allow homes in the city to be sold to non-Marathis?

This kind of gross bigotry is astounding...even for a country like India.