Infosys Ltd said on Tuesday it was investigating allegations of "unethical practices" by Chief Executive Officer Salil Parekh after receiving whistleblower complaints last month, sending its shares into a tailspin.
One of the complaints "largely deals with allegations relating to the CEO's international travel to the US and Mumbai," Infosys Chairman Nandan Nilekani said in a statement.
Parekh did not respond to Reuters' request for comment.
Infosys shares plunged 16 percent on Tuesday, marking their worst intraday drop in over six years.
The allegations come just two years after India's No. 2 software services firm endured a shakeup that saw its top boss Vishal Sikka leave the company.
The Economic Times had reported on Monday that an anonymous group sent letters to Infosys' board and the U.S. Securities and Exchange Commission alleging that the company was taking "unethical" steps to boost short-term revenue and profit.
The group alleged that Parekh was bypassing reviews and approvals for large deals, the report added.
Infosys said it placed the complaints received in September before the audit committee on Oct. 10, and before the non-executive members of the board on Oct. 11.
The complaints are being dealt with in an objective manner, with the CEO and Chief Financial Officer Nilanjan Roy recused from the matter, it added.
The audit committee has retained the law firm of Shardul Amarchand Mangaldas & Co to conduct an independent investigation, and the company's board will take appropriate steps based on the outcome of the investigation, the company said.