Lucknow, Feb 7 (IANS): The Class 10 and 12 examinations conducted by the Uttar Pradesh government began amid tight security on Thursday with magistrates, police on high alert, besides the introduction of coded answer sheets to prevent any foul play, officials said.

A total of 58,06,922 students have enrolled for these exams which were being conducted at 8,354 examination centres.

There are 31,95,603 students taking the Class 10 or the Higher Secondary exams, while 26,11,319 were writing the Class 12 or the Intermediate exams.

Uttar Pradesh Board Secretary Neena Srivastava told IANS that District Magistrates (DMs), police chiefs and even the Special Task Force (STF) were on vigil to take on organised crimes.

They have been tasked to ensure that there was no cheating and unfair means adopted by the students during the conduct of the annual exams.

For the first time, she informed, coded answer sheets were being used in which roll numbers has to be written on every page to ensure that there is no change of copies.

"We always received complaints that the copies have been changed but now because of the new rules, this would not be possible as the students will write their roll numbers themselves.

"In case of an eventuality that an allegation of answer sheets altered is made, the handwriting will be examined," she added.

According to Board officials, 1,314 examination centres have been identified as "sensitive" and 448 "very sensitive".

This demarcation has been done on the basis of the past track record of mass cheating in these places.

Mobile squads under magistrates would be conducting surprise checks and ensure that there was no copying. Some 2.50 lakh invigilators were on duty.

Deputy Chief Minister Dinesh Sharma, who also holds the basic education charge has been making efforts to cleanse the system, which has been virtually destroyed by the copying mafia over the years.

Sharma also visited some centres in the state capital to check the ground level preparations.