The decision was taken in the Cabinet meeting chaired by the chief minister.
"People have raised a lot of doubts in the manner in which the investigations have been conducted. Fingers have been pointed at the lapses from the postmortem to cremation. We've decided to change the investigating team which will now be led by a woman officer, ADGP B Sandhya," Mr Vijayan told the media.
The 30-year-old Dalit student was raped, mutilated and murdered on April 28, but nearly a month later, no arrests have been made.
Mr Vijayan, 72, was chosen over 92-year-old veteran VS Achutanandan as the chief minister despite the latter's mass appeal. Mr Vijayan has a reputation of being an extremely tough and stern politician and administrator.
Even as a chief ministerial-designate, Mr Vijayan took a strong stand against corruption. His cabinet mostly consists of first time ministers, with the five experienced ministers as exception. Pinarayi Vijayan has kept the important portfolios of Vigilance and Home with himself. In the last few days, there have been deliberate attempts by the now Chief Minister to portray a more approachable and friendly disposition.
While his predecessor Oommen Chandy met the media every Wednesday to brief them about the Cabinet decision, Mr Vijayan has indicated that that may not to be the norm.
"We don't have to meet every Wednesday," he told the media after his first Cabinet briefing.
From a toddy tapper's son, to Kerala CPM's longest serving state secretary, Mr Vijayan took his oath as the 22nd chief minister of Kerala in a packed central stadium in Thiruvananthapuram. It is estimated that more than 30,000 people were present, including the top party leaders. CPM's 'Fidel Castro', Mr Achuthanandan was seated next to former UDF chief minister Oommen Chandy.
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