A string of mysterious deaths linked to a high-profile bribery scandal has prompted outrage in India, as the country struggles to shed its reputation for endemic corruption.

Politicians, bureaucrats and businessmen are alleged to have been involved in manipulating the selection process for thousands of government jobs and places at professional colleges in the central state of Madhya Pradesh on a huge scale since at least 2007.

While Indians are typically jaded with news of official wrongdoing, this scandal – known as “Vyapam” after the Hindi acronym for the state’s examination board – has captured public attention, largely due to the body count it has apparently left in its wake.

At least 30 people accused of facilitating or benefiting from the scam have died since it first came to light – some seemingly from illness, while others were killed in car crashes or apparently took their own lives. But the tally has left many activists cynical. “It is not a coincidence that all the accused are dying of one ailment or another. There is something more to it,” Prashant Pandey, who first blew the whistle on the scandal, told the Press Trust of India. Mr Pandey has said he fears for his own life.

Indian Youth Congress workers scuffle with police as they protest in Bhopal, India (EPA)

The latest deaths include a young national television journalist covering the case, who began foaming at the mouth and collapsed during an interview with the family of a girl who herself died after being accused of cheating in exams.

Also in the last few days, a policeman who had been questioned in connection with Vyapam was found hanging from a ceiling fan and a trainee policewoman allegedly recruited through the crooked process was found dead in a lake.

Elsewhere in the country, the body of the dean of a medical college implicated in the cheating was discovered in a Delhi hotel room on Sunday.

More than 2,000 people, including Madhya Pradesh’s former Education Minister, have been arrested in connection with the case since 2013, when an investigation team was set up by state police.

The cheating was thought to be systemic and sophisticated. In return for kickbacks, in some cases imposters were allowed to take tests instead of the real candidates, while in others applicants were asked to leave their exam sheets blank so that they could be filled in later to match a high score that had been fraudulently awarded.

But the latest deaths have now forced Madhya Pradesh’s Chief Minister, Shivraj Singh Chouhan, to heed calls for the inquiry to be reassigned to a federal body.

“I do not want to leave anybody in doubt about over our intention to clean the system and punish the guilty,” Mr Chouhan said in a statement posted on his Twitter account, after requesting a central investigation.

Shivraj Singh Chouhan, Madhya Pradesh’s Chief Minister (Reuters)

Mr Chouhan denies claims made by opposition politicians that he and other officials benefited from the fraud. He said it was he who first ordered the state police to look into the exam body and cautioned against linking any of the deaths to the investigation.

The allegations against Mr Chouhan, a member of the ruling BJP party, has put pressure on Prime Minister Narendra Modi, who made tackling corruption in India a key plank of his tenure.

Mr Modi secured a resounding victory in India’s general election last year over the opposition Congress party, which had been plagued by allegations of corruption during its time in office, and he promised a fresh start.

But his government has also been hit by claims last month that his Foreign Minister used her connections in the UK to help expedite a visa appeal made by the former cricket tycoon Lalit Modi, who moved to London after being accused of corruption in India.

The Vyapam scandal, with its many unanswered questions and intrigue, has been pounced upon by a flagging Congress party to try to reinvigorate its fortunes both in Madhya Pradesh state and nationally.

“There are very powerful big people involved in this,” said the Congress party’s Digvijaya Singh, a former Chief Minister of the state, who is calling for India’s Supreme Court to oversee the investigation.

Jobs with local government departments in India and places on top professional courses are highly coveted for their prestige and security, fuelling intense competition among applicants.