India, Oct. 31 -- An India-origin CEO of a little-known telecom-services company in the US has emerged at the centre of what has been described as a "breathtaking" fraud in an opaque corner of the US debt markets.

A unit of Blackrock Inc. and other lenders are trying to recover hundreds of millions of dollars that they gave to Bankim Brahmbhatt, owner of Broadband Telecom and Bridgevoice, as loan collateral, according to WSJ. The lenders-who filed the lawsuit in August-said that Brahmbhatt's companies owe them more than $500 million.

Brahmbhatt disputes the allegations of fraud, his lawyer said.

BNP Paribas helped BlackRock's HPS Investment Partners finance Brahmbhatt loans, people familiar with the matter said. A spokesman for the Fre...