( 1 ) THE petitioners numbering six by this petition filed under Article 226 of the Constitution seek a mandamus directing respondents I and 2 to stop and prohibit the third respondent from commencing/carrying on any commercial activity in the property beang No. D-1097, New Friends Colony, New Delhi, and further restraining the third respondent from carrying on any unauthorised construction in the property. Mandamus is also sought directing respondents I and 2 to proceed against the third respondent under the provisions of the Delhi Municipal Corporation Act, 1957, and the Delhi Development Act, 1957. The First respondent, as seen above, is the Municipal Corporation of Delhi (MCD) and was constituted under the Delhi Municipal Corporation Act, 1957 and is charged with various functions as mentioned in that Act relating to the municipal government in Delhi; the second respondent is the Delhi Development Authority (DDA) and was constituted under the Delhi Development Act, 1957, which Act provides for development of Delhi according to plan and further matters connected therewith; and third respondent is Vinod Sachdeva, occupier of property bearing No. D-1097, New Friends Colony, New Delhi. Delhi Development Authority in its affidavit has said that Smt. Bimla Devi Sachdeva is the sub-lessee/allottee of the aforesaid property. The property is built on a plot of land measuring 283. 9 sq. yds. abutting on a 30 ft. wide road in the colony. Five petitioners are the immediate neighbours of the third respondent and one petitioner is also in the neighbourhood.

( 2 ) THE petitioners contend that the land use of the property bearing No. D-1097 and of their houses as well is residential and it cannot be used for commercial purposes or use and that will be contrary to the Delhi Development Act, 1957 (DD Act), the rules and regulations framed thereunder, under the Master Plan, the Zonal Plan and the Layout Plan of the colony, all being statutory in nature. They further contend that use of the property in question for any other purpose except residential is again illegal and contrary to the provisions of Delhi Municipal Corporation Act, 1957 (DMC Act ).

( 3 ) THE immediate cause for filing this petition was that the third respondent was going to commence the full-scale commercial activity in the property in question in the nature of safe deposit lockers which would not only be against the provisions of the DD Act and DMC Act but also would result in a public nuisance. Petitioners further say that for the purpose of conversion of the residential premises into commercial one certain unauthorised constructions were also going on in the property. When the petitioners found that more than 500 lockers were being lifted from truck outside the property and were being stored therein they immediately wrote letters to the authorities concerned, but since no action was taken, this petition was filed.

( 4 ) THERE is no dispute that in the basement of the property the third respondent proposes to start the activity of safe deposit vaults. Since the property is built on a plot held on leasehold basis we required the second respondent Delhi Development Authority to file an affidavit on three points: (1) whether the property in question is being put to residential use or commercial use fully or partly; (2) whether the alleged commercial activities are in fact commercial activities interms of the perpetual lease respecting the plot in question; and (3) what action Delhi Development Authority intends to take if it is of the opinion that the alleged activity is a commercial one. We also wanted a report from the Delhi Development Authority what action it proposed to take in the matter if it found that any term of the lease deed had been contravened. In pursuance to our order, Delhi Development Authority filed a supplementary affidavit. The stand of the Delhi Development Authority is that the property in question is to be used for a purely residentia