Students have claimed that the HSC book-keeping and accountancy paper was 'leaked' at least 30 minutes before it was handed out to examinees on Monday.
It is reported that screenshots of the question paper were distributed on WhatsApp.
While prima facie, the Board has refrained from calling this a paper leak as shots were circulated on WhatsApp after the exam started.
A report by the Mumbai divisional office has been submitted to the Maharashtra State Board for Secondary and Higher Secondary Education (MSBSHSE) in Pune, which will decide the future course of action.
"At 11.26am, we received the pictures through journalists. We do not have proof that the pictures were circulated before the paper began and hence, we will treat it as a case of cheating," said Y S Chandekar, secretary, Mumbai divisional board.
The board rules bar students from carrying mobiles to exam centres, but in reality, most bring them to classrooms and are told to switch them off and keep in bags. Students are not frisked. Exam coordinators said many parents insist on the phones as many students travel from far.
The Pune officials have received a report from the Mumbai divisional office and are setting up an inquiry committee to investigate the issue.
Over three lakh students took the exam, and officials claimed the incident was limited to Mumbai division. "We received complaints from Mumbai division. It looks like a copying case prima facie. We are investigating. As of now, re-exam is not being discussed," said Krishnakumar Patil, secretary, Maharashtra State Board of Secondary and Higher Secondary Education.
Sources said students in Kandivli were among the first to get shots of the first three pages of the 11-page paper. The pages contained objective questions of 15 marks and part of an eight mark sum.