New Delhi (AFP) – India blocked access to Telegram messenger on Tuesday ahead of a retest of a nationwide medical college entrance examination, after a scandal last month over a question paper leak.

The failure of the hugely competitive exam, along with a separate marking fiasco in high school tests, sparked outrage and fuelled youth protests demanding the education minister's resignation.

The Ministry of Electronics issued the order restricting access to Telegram until June 22, the day of the retest. Message-editing features, which allow users to alter existing posts, will remain restricted until June 30.

"Both measures have been taken in the interest of public order, in response to the organised use of the platform by cheating rackets to defraud candidates," India's National Testing Agency (NTA) said in a statement.

The National Eligibility Entrance Test (NEET) is one of the country's most competitive exams, attracting more than two million aspiring doctors.

The NEET exam was scrapped in May following allegations that the question paper was leaked in advance, including reports that it had been circulated through Telegram channels.

The intense pressure to succeed in these exams has fuelled a lucrative industry, with tens of thousands of coaching centres across the country.

Fierce competition means that success often comes at a significant personal and financial cost -- creating opportunities for criminal networks seeking to sell leaked examination papers to the highest bidder.

India's Central Bureau of Investigation has arrested the "kingpin" alleged to be behind the leak, naming him as a chemistry lecturer involved in the examination process for the NTA.

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