New Delhi (CNN) TV journalist Akshay Singh had spent about an hour talking to the family he had traveled to central India to interview when he started losing consciousness.

Singh foamed at the mouth and fell from his chair, according to colleagues. His TV crew took him unconscious to a nearby hospital where he was declared dead.

The next day, police in New Delhi found the body of a college dean, Arun Sharma, in a hotel room.

On the face of it, the two deaths over the weekend, which happened hundreds of kilometers apart, have nothing to do with each other.

But both men are linked to a mysterious web of suspicion, death and scandal that has seized national attention in India and prompted one government minister to say she fears for the lives of those connected to her.

At the heart of the matter is a high-profile corruption case involving allegations of bribes being paid for jobs and college admissions in the central Indian state of Madhya Pradesh.

Corruption is hardly unusual in India. What's causing alarm in Madhya Pradesh is that people connected to the state's investigation into the alleged scam keep dying.

'I am a minister but still I am scared'

A former judge supervising the state's investigation has said that more than two dozen people linked to the case have died in the past two years.

Opposition politicians and activists in Madhya Pradesh allege that the number of deaths is almost double the official count.

Many of the deaths were originally attributed to causes like road accidents, suicide and illness. There's no evidence of foul play, but many Indians don't know what to believe anymore.

"I am scared for the lives of people connected to me. I am a minister but still I am scared," Uma Bharati, the water resources minister for India's federal government and a former chief minister of Madhya Pradesh, said Monday, according to The Times of India, a national newspaper.

Deaths at weekend under investigation

The two men who died over the weekend both had links to the scandal, which investigators say dates back to at least 2007 and involved a nexus of politicians, bureaucrats, middlemen and bribe-paying candidates.

Singh was working on a report about the death of a suspect who had been named in the investigation. He collapsed Saturday during a visit to the suspect's family in Madhya Pradesh.

"He was making sound like he was choking on something," Rahul Kariya, a colleague who was with him at the time, said in an interview with India Today, their employer. "His left hand became stiff and his lips quivered."

Akshay's family says he had no medical illness. Had not visited a doctor in many years. Was fit. Exercised. No alcohol. No cigarettes. — Rahul Kanwal (@rahulkanwal) July 4, 2015

Authorities say Singh had no signs of internal or external injury. But they have sent samples from his body to forensic experts to determine the cause of death.

The India Today Group has called for an independent inquiry into his death.

"The circumstances of the untimely death of TV Today journalist Akshay Singh merit a full, fair and independent inquiry," the company said. TV Today is the television arm of the India Today Group.

Shocked to hear about mystery death of fellow journalist Akshay Singh. Our best tribute would be to unearth the truth in #VyapamScam — barkha dutt (@BDUTT) July 4, 2015

The death the following day of Sharma, a college dean from Madhya Pradesh who had been helping investigators, intensified the growing political storm surrounding the scandal.

Police say they don't suspect anything untoward in Sharma's death but they have set up a special medical board for an autopsy.

'The truth behind the deaths must come out'

The intense interest in the case is heaping pressure on Madhya Pradesh Chief Minister Shivraj Singh Chouhan.

He set up the special task force investigating the scandal. But critics said he hasn't done enough.

The investigation "seems to have no answers for the spate of suspicious deaths," said an editorial over the weekend in The Hindu, a national newspaper. "Worse still, State government officials have appeared callous in their responses and have attempted to just shrug off the matter."

On Monday, the opposition Congress party demanded that Chouhan be fired and the case handed over to federal investigators.

"The truth behind the deaths must come out," said Randeep Surjewala, a Congress spokesman.

In an apparent concession, Chouhan announced Tuesday that he would request a federal investigation into the scandal and the deaths.

But Chouhan, a member of Prime Minister Narendra Modi's governing Bharatiya Janata Party, rejected his opponents' attacks against him as baseless.

"Their only objective is to target me and tarnish my reputation," he said at a news conference.

More than 2,500 suspects

The scale of the investigation is vast -- it has named more than 2,500 people as suspects accused of forgery and impersonation. But about 500 of them still haven't been tracked down and arrested yet.

Under the alleged scam, candidates are alleged to have paid hefty bribes to either pass exams for state government jobs or for admission to higher-educational institutions.

In many cases, students were paid to use forged admission cards to impersonate candidates and write tests for them in connivance with officials, according to police. Funds worth millions of dollars are reported to have been involved in the scheme.

The full scale of the scandal came to light in 2013 after police arrested imposters who were taking a medical test conducted by Madhya Pradesh's professional examination board.

The board, known as Vyapam in Hindi, conducts competitive exams for admissions to medical and engineering colleges and for employment in police, forest and education departments of the state government.

The word Vyapam has become synonymous with the scandal in India.