A portion of the Madhyamik Bengali first language question paper was circulating on WhatsApp while the examination was in progress on Tuesday.

The West Bengal Board of Secondary Education, which conducts Madhyamik, filed an FIR with the Bidhannagar police commissionerate, requesting it to find out how the paper surfaced on the messaging app despite the board taking several measures this year to ensure that no one enters an examination centre with a mobile phone.

Board president Kalyanmoy Ganguly said a board official received a WhatsApp message on his phone with the picture of the front page of the Bengali first language paper. Board officials immediately examined the image and found it to be of the Bengali first language paper.

Ganguly ruled out the possibility of a “leak” as there was no evidence to show the paper had been circulated before the start of the examination.

The examination began at 11.45am and the board received the picture on WhatsApp at 1.43pm.

“The board’s deputy secretary (examinations) received a WhatsApp message around 1.43pm with the image of the first page of the Bengali first language question paper. We examined the page and found it to be exactly the same as today’s paper. We filed an FIR with the Bidhannagar police, requesting them to identify the sender,” Ganguly said.

Some members of the media, too, received the WhatsApp message with the picture of the question paper.

Students as well as teachers and non-teaching employees of schools are barred from carrying mobile phones to the examination halls.

Teachers and non-teaching staff have been asked to switch off their phones and hand them over to the head of the institution, who must keep the devices under lock and key till the examination is over.

Only a few board officials — the officers in charge of the venues, the school heads who are the centre secretaries, venue supervisers and additional venue supervisers — are allowed to carry mobile phones during the exam but the phones can only be used to communicate with other board officials on any exam-related matter.