India, June 3 -- The U.S. Justice Department is reportedly investigating Indian billionaire Gautam Adani's business empire over alleged violations of Iran sanctions. The inquiry may significantly escalate the legal troubles already surrounding the industrialist.

A Fresh Allegation Amid Existing Charges Gautam Adani, Asia's second-richest man and chairman of the Adani Group, is facing renewed scrutiny from U.S. prosecutors. The Wall Street Journal reports that the U.S. Department of Justice is now investigating whether Adani's companies illegally imported Iranian liquefied petroleum gas (LPG) into India.

This comes just months after Adani was charged with orchestrating $250 million in bribes to Indian officials to secure solar-power cont...