Police have arrested two more teachers and an office assistant of a school in connection with the Secondary School Certificate test question paper leaks in Kurigram's Bhurungamari Upazila.
Police brought them in for questioning on Wednesday but were shown arrested in the case over the incident on Thursday.
The arrestees are Sohel Al Mamun, a Bangla teacher of Bhurungamari Nehal Uddin Pilot Girls High School, Hamidul Islam, a physics teacher and Sujan Mia, a clerk.
Earlier on Wednesday, three people, including the headmaster of the school, were arrested.
Alamgir Hossain, chief of Bhurungamari Police Station, said the three newly arrested were sent to jail through the Kurigram Chief Judicial Magistrate Court on Thursday.
District Education Officer Shamsul Alam said that on behalf of the director general of the Directorate of Secondary and Higher Education, or DSHE, he started a preliminary investigation after visiting the school on Thursday. He recorded the statement of assistant headmaster Khalilur Rahman and other teachers.
No one involved in question paper leaks will be spared, said Shamsul, adding that the DSHE is investigating whether the negligence, irregularities or corruption of any member of the directorate led to the leaks.
Departmental action will be taken against those involved, he said.
A three-strong investigation committee formed by the Dinajpur education board has already reached Kurigram. They have also started their investigation process.
Police sought a three-day remand of Lutfar Rahman, the headmaster of the school, while the accused sought bail and the judge set Sept 29 for the hearing of the petitions.
The authorities moved after allegations of leaking the question papers of English 1st and 2nd papers of the current SSC examinations surfaced on mainstream and social media.
Question papers were found in the headmaster's room on Tuesday. Headmaster Lutfar, English teacher Aminur Rahman Russell and contractual teacher Zubair Hossain were arrested in connection with the case.
On Wednesday, the Board of Intermediate and Secondary Education, Dinajpur postponed the tests on four subjects. New dates were announced on Thursday.