Secretary of the Delhi government's Services Department, Ashish More was removed from his post on Thursday, hours after the Supreme Court gave the Aam Aadmi Party dispensation control over the transfer and posting of officers in the city, officials said.
Former Delhi Jal Board CEO A K Singh, a 1995-batch (AGMUT cadre) IAS officer, will replace More.
Sources from the Services Department, however, claimed that the order issued by the government was 'illegal'.
According to officials, the Supreme Court had directed the Centre and states to establish a Civil Services Board.
The Board's mandate was defined to consider transfers of bureaucrats.
The Committee on Minimum Tenure or Civil Services Board shall examine the cases of officers who are proposed to be transferred before completion of minimum tenure, according to rules. It shall seek a detailed justification in the matter.
The Delhi government constituted the CSB in 2014.
However, in the case of More, this rule of first putting up the matter for CSB consideration was not followed.
Earlier in the day, the apex court pronounced that the Delhi government has legislative and executive powers over administration of services except for matters relating to public order, police and land.
Chief Minister Arvind Kejriwal, in a press conference, said there will be a major administrative reshuffle in the government, warning of action against officers who 'obstructed' public work.
Prior to the verdict of the court, the Services Department was under the control of Delhi's Lieutenant Governor.
