Hundreds of Class 12 students in Bihar who have failed in their exams continued their protest for the fourth consecutive day in Patna on Saturday demanding re-checking of their answer sheets and action against top officials, police said.

More than eight lakh of the over 12 lakh students who appeared for the Class 12 exams conducted by the Bihar School Examination Board (BSEB), failed this year. The results were declared on Tuesday.

The angry students, led by the CPI-ML student wing AISA, staged a protest outside the Bihar Inter Council office and reportedly damaged the windows of a bus besides blocking roads and pelting stones at the police, officials said.

"We want re-examination for all and action against the BSEB chairman," a protesting student said.

The police resorted to baton-charge to disperse the protesters but failed as the slogan shouting students returned outside the Council office and continued their protest despite the scorching heat.

"Hundreds of students protested for the fourth day and raised slogans against Bihar Chief Minister Nitish Kumar, Bihar Education Minister Ashok Choudhary and BSEB chairman Anand Kishore over the poor results," a police official said.

Similar protests also took place in Vaishali district on Saturday.

The students were led by the CPI student wing AISF and the RSS' student wing ABVP during their protests on Wednesday, Thursday and Friday.

In a repeat of last year's events, the BSEB on Friday cancelled the result of Class 12 topper in the Arts stream Ganesh Kumar and arrested him for committing forgery among other charges.

Patna Senior Superintendent of Police Manu Maharaj, who interrogated Ganesh after he was produced in the local court on Saturday, told media he confessed that he had fudged his age to appear in the examination.

Chief Minister Nitish Kumar has assured that the failed students can apply online for re-evaluation or verification of their answer sheets and these results will be out within a month. He also promised the BSEB will hold compartmental exams soon.

The pass percentage of students of Science, Arts and Commerce streams was 35.24 per cent this year as only 4,47,115 students passed of the total 12,40,168 students who appeared in the exams, after the authorities implemented strict measures against cheating.

Last year, the total pass percentage was 62.19 per cent. It stood at 87.45 per cent in 2015, 88.04 per cent in 2013 and 90.74 per cent in 2012.

A senior BSEB official said the drastic fall in pass percentage vindicated their strict efforts to conduct cheating-free examinations.

This year, CCTV cameras were installed at entrances of the examination halls and videography was conducted throughout the duration of the exam.

Use of all communication gadgets, including mobile phones, inside the examination halls was prohibited.

Mass cheating in board exams has been rampant in Bihar for years.