New Delhi, March 29: The Congress on Thursday targeted Prime Minister rendra Modi over the CBSE paper leak and sought sacking of Human Resource Development Minister Prakash Javadekar as he expressed his determition to bring the guilty to book. The Delhi Police, which has interrogated 25 people, said it was trying to reach the “point of origin” of the leak of the mathematics and economics papers for Class X and Class XII circulated through WhatsApp ahead of the examitions. Students lodged their protest at Jantar Mantar against the Central Board of Secondary Education over the exam leak by carrying placards and raising slogans. Breaking her silence on the paper leak, CBSE Chairperson Anita Karwal assured students that the board will soon announce fresh dates for mathematics and economics examition.