The school principal of the juvenile accused in the December 16 gangrape-cum-murder case on Monday appeared before the Juvenile Justice Board in response to its summons to help determine his exact age.
The JJB is believed to have expressed its dissatisfaction over the documents placed before it to determine the veracity of the age of sixth accused, who claims to be 17 years.
The JJB found the documents produced by the principal as insufficient, sources said.
The Board had asked the principal of the school in Badaun in Uttar Pradesh, where the juvenile had purportedly done his initial schooling, to appear before it with some documents.
The Board has now asked the principal to appear again on January 15 and furnish more authentic documents which can assist them in ascertaining the age of the accused.
The juvenile accused also appeared before the Board comprising three members.
While the juvenile accused is at present lodged in juvenile home, the other five adult co-accused are lodged in Tihar jail and are being proceeded against in a Saket court.
The five accused, Ram Singh, his brother Mukesh and their accomplices Pawan Gupta, Vinay Sharma and Akshay Thakur have been charge sheeted for the offences of murder, gangrape, attempt to murder, kidnapping, unnatural offences, dacoity, hurting in committing robbery, destruction of evidence, criminal conspiracy and common intention under the Indian Penal Code.
While the charge sheet describes the role of the juvenile accused, the police has not named him in it because of his age.
A separate charge sheet will be filed against him after ascertaining his age.
The result of bone age test of the juvenile, who the police said was the most aggressive of the six accused in the crime, is awaited.