India's Supreme Court rejected an appeal Monday against the release of the youngest convict in an infamous fatal gang-rape in 2012, saying there were no legal grounds for his continued detention.

"The Supreme Court has dismissed our plea in the absence of any specific legislation. He cannot be detained any further," said Swati Maliwal, the chairwoman of the Delhi Commission for Women which filed the petition.

"We asked for an interim order restraining his release but the court did not entertain this," she told reporters.