The CID has already made three arrests in the case, an officer told PTI.

"We have detained students, teachers and others across Assam. They have been brought to Guwahati for further questioning," the officer said, without sharing further details.

On Monday, the Assam Police registered a criminal case and handed over the investigation to the CID. Director General of Police (DGP) GP Singh took to Twitter yesterday to announce that 22 people had been detained from Guwahati, North Lakhimpur, Dhemaji, Sadiya, Dibrugarh and Tinsukia.

Assam Police Spokesperson Prasanta Kumar Bhuyan had told PTI that the three arrested were all from the Government Deaf and Dumb School in Guwahati. "They are all from the Government Deaf and Dumb School, Kahilipara in Guwahati. There were 42 packets of question papers meant for the school, but one was missing. This is a strong ground to arrest them," he said.

The arrested persons include the principal, a teacher and a casual employee of the school, Bhuyan, the Inspector General of Assam Police (Law and Order) said.

Meanwhile, education minister Ranoj Pegu said that the CID is investigating to get to the root of the paper leak. "Some students and others have been arrested or detained so far. But we have to be patient and need to wait for the CID probe to be over to know from where the paper leak originated," he said.

The interrogation comes amid protests by student and youth organisations in Assam who have demanded the resignation of the state education minister over the leaking of the General Science question paper. All Assam Students’ Union (AASU), National Students’ Union of India (NSUI), Satra Mukti Sangram Samiti (SMSS), All Bodo Students Union (ABSU) and Asom Jatiyatabadi Yuva Chhatra Parishad (AJYCP) held demonstrations and burnt effigies of Pegu at several places of the state.

The opposition Congress also held a demonstration at the Assembly gate before the start of the day's proceedings, demanding clarity over the issue.

"The government told us in the House that the examination was cancelled as some materials were [shared] on WhatsApp. They must clarify what had actually happened," Leader of Opposition Debabrata Saikia said.

The general science exam of the Board of Secondary Education, Assam (SEBA) for class 10 was cancelled late on Sunday night, following reports of leakage. The SEBA notified that the cancelled examination of general science will now be held on March 30.
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