"A magisterial inquiry has been ordered in the case," Gurgaon District Magistrate P C Meena told PTI.
He said a case has also been registered against Rohatash Tayal, the landowner who had dug up the borewell.
Tayal has been absconding and the state police have sent out two teams to trace him.
Meanwhile, Haryana Chief Minister Bhupinder Singh Hooda condoled the death of Mahi and said her family would be adequately compensated.