An alleged attempt to sabotage the helicopter of India's second richest man, Anil Ambani, is developing into a full-blown murder mystery after the mechanic who discovered the plot was suddenly killed this week.
The helicopter's mechanic, Bharat Borge, was found dead on a city railway track on Tuesday. The Mumbai government said it was suicide but his family is alleging foul play and calling for a federal police investigation.
"He did look tense over the past few days but he never seemed like the type of person who might commit suicide," said Sambhaji Botre, the deceased's cousin. "He would have first spoken to the family."
The mechanic found mud and pebbles in the petrol tank of Mr Ambani's helicopter last Thursday, the night before the Bell 412 owned by the billionaire's Reliance ADA Group was due to take him to his office on the far side of Mumbai.
The alleged sabotage attempt, which was detailed in a police complaint filed by the mechanic's company, captured the headlines of India's domestic tabloids because of Mr Ambani's reputation as one of Mumbai's most prominent businessmen.
The younger son of Dhirubhai Ambani, one of India's most successful industrialists, Mr Ambani presides over an empire that spans telecoms, capital markets and movies, including a tie-up with Steven Spielberg's DreamWorks.
Several years ago, Mr Ambani's mother divided his late father's business empire up between him and his estranged brother, Mukesh Ambani.
Since then, the pair have fought several highly public battles. Last year, Mukesh scuppered a proposed deal between Anil's Reliance Communications mobile phone group and South Africa rival MTN that would have been worth up to $40bn.
Mukesh Ambani is India's richest resident Indian with a net worth of $20.8bn while Anil Ambani is the second richest with $12.5bn, according to Forbes.
Mr Ambani lives in plush south Mumbai but commutes in his helicopter to Reliance's headquarters on the outskirts of India's congested financial capital a few time a week.
Fredrik Groth, the chief executive officer of Air Works India, the company that maintains the helicopter, said: "We have been fully co-operating with the investigation - we were the first ones to report the anomalies."
He said the discovery of gravel or pebbles in the fuel tank was a "first" in his experience.
"This was a one-off accident - we never had these kinds of problems in the past."
Police had already opened an investigation into the case. But it took a bizarre twist with the death of Mr Borge, who police say died of his injuries after being hit by a train.
Jayant Patil, the home minister of Maharashtra state, of which Mumbai is the capital, insisted the death was a suicide and rejected suggestions the case should be handed over by the state police to the central government's Central Bureau of Investigation.
"There were some witnesses who saw him committing suicide," said Mr Patil.
He also dismissed allegations Mr Ambani may have been the target of an enemy in the business world.
"The investigation so far does not give any clues to any corporate rivalry," Mr Patil said.
Copyright The Financial Times Limited 2009