The invigilators are provided question papers at 9.45 am on the examination day and are allowed to open the question papers immediately. The exam starts at 10.30 am.
However, in this case, the school authorities allegedly provided the question papers to teachers around 9.10 am, which gave the two accused -- Rohit and Rishabh -- ample time to click the pictures and send to Tauqeer, a tutor at a private coaching centre, who circulated them to the students, the official said.
He said the police are also probing whether the school had provided question papers of other subjects to the teachers before the scheduled time and whether those were also leaked.
Police have questioned the principal and five teachers of the school in connection with the matter. They have not been given a clean chit, said the official.
Three men, including two teachers from the school, were arrested on Sunday for their alleged involvement in the Class 12 economics paper leak.
The Delhi Police has registered two cases in connection with the leaks.
The first case relating to the leak of the economics paper was lodged on March 27 and the other pertaining to the mathematics paper was lodged on March 28, following a complaint by the regional director of the CBSE.
The Class 10 mathematics and Class 12 economic papers were held on March 28 and March 26 respectively.
The Crime Branch has questioned over 60 people in connection with the CBSE leak case, including the administrators of over 10 WhatsApp groups on which the leaked question papers were shared.
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