"Police beat him up, hung him upside down, tortured him and even sedated him to make him confess," Kumar's wife Mamata told ANI.
Kumar, accused in the Pradhyumn murder case, was released on bail from Gurugram's Bhondsi jail late on Wednesday night.
He thanked the media for his return to his family and said he is in a lot of pain.
Mamata also said that Kumar told her that a 'madam' asked him to keep the body (of Pradhyumn) in the car and that he just helped. He had no idea that the police and the authorities will target him on that basis.
She alleged that the police injected him as well.
"The police asked him to say that he committed the crime and assured he won't be in trouble. They told him that the whole nation is distressed due to the case and so he must confess. The police told him it's a small case and they will cover it accordingly," Kumar's sister-in-law told ANI.
The family also alleged that he was forced to put the child in the car and when his shirt got blood stained, he was asked to wash it.
"He got blood on his shirt, and the authorities asked him to wash his clothes and he was told that the child is fine," Kumar's family said.
They also said when the child was admitted to the hospital and died later, Kumar was immediately captured and was tortured.
"The authorities from top down are working together and have forcefully made a poor man suffer. Now our lawyer will deal with them," the family said.
The Gurugram District Court granted bail to Kumar on Tuesday on a bond of Rs 50,000.
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