The names of over 20 lakh students were struck off from about 70,000 schools across 38 districts in Bihar.
This comes after the state government asked schools to deregister students for remaining absent for prolonged periods without informing authorities.
More than 1.5 lakh students are at risk of missing board exams.
Schools were initially asked to remove students if they remained absent for 30 days. The period was later revised to 15 days and then to just three days.
Teachers’ associations opposed the move, calling it “arbitrary” and an “infringement” of the Right to Education Act.
They said they would challenge the decision before the National Commission for the Protection of Child Rights.
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