The victim's father, said the central probe agency had failed to file a strong chargesheet and that it was yet to conclude its probe in the case.
"We are very disappointed. We expected the CBI to file a strong chargesheet," he said.
His lawyer also said the CBI, being a mature and premier investigating agency of the country, should have concluded its probe in the case.
The lawyer also said the CBI should have named the owners of the school and the officials of the Gurgaon police's Special Investigation Team (SIT).
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