Ahmedabad, June 17: A rich NRI is found clubbed to death outside a posh club. He is carrying a letter telling an American private detective that a powerful Gujarati religious sect plans to kill him.

The latest murder mystery in Ahmedabad has had police flummoxed despite the rather explicit lead.

The body of 52-year-old businessman Pankaj Trivedi, who had emigrated to Cincinnati in America nine years ago, was found near his car, parked outside the posh Ellisbridge Gymkhana on Thursday night.

Inside the car was a neatly filed copy of a signed letter, addressed to Todd R. Bagby, a detective in Dayton, Ohio. The letter, dated May 19, 2006, seeks “protection for me and my family from the leader and fanatical followers” of Swadhyay Parivar ? a sect enjoying a huge following in the state and in the US ? “whose unethical and illegal activities I have exposed”.

Over the past five years, Trivedi has filed several cases in Gujarat’s courts accusing the sect, among other things, of misusing funds raised for humanitarian purposes. This allegedly includes $4.2 million (Rs 20 crore) raised in the US after the 2001 Gujarat quake.

“On April 1, 2006, outside the Newark Airport (in New Jersey),” the letter says, “four unknown people threatened me and asked me to stop? exposing the unethical work of Swadhyay.”

Assistant police commissioner R.S. Chudasama said the police cannot take any action based on the letter. “We can’t question any member of this sect unless a formal complaint is lodged,” he said.

Trivedi’s local friends said he had told chief minister Narendra Modi and state home minister Amit Shah about the threat to his life.

Swadhyay Parivar was founded about half a century ago by Pandurang Shastri. Since his death, it has been headed by his niece, “Didi” Jayshree Talwalkar.