The Infosys audit committee has already sprung to action and fast tracked the investigation on the whistleblower complaint against Infosys CEO Salil Parekh and CFO Nilanjan Roy. The audit committee is likely to question former CFO MD Ranganath and former deputy CFO Jayesh Sanghrajka about the allegations, people aware of the development told CNBC-TV18.Earlier this week, a letter by a whistleblower group that called itself "ethical employees" came to light, levelling serious allegations against the Parekh and Roy. These included complaints of profit inflation, fraudulent accounting, irregularities in large deals and employees being asked to not recognize finance costs.Following this, shares of the IT services major got pummeled in trade on Tuesday. On the NSE the stock fell 16.5 percent to close at Rs 640. The sharp fall in the scrip wiped out Rs 53,450 crore from the company's valuation .On October 21, the audit committee retained the law firm of Shardul Amarchand Mangaldas to conduct an independent investigation into the allegations. Infosys also published a letter by Nandan Nilekani that gave a detailed timeline of events in question.It outlined that on October 16 the company was made aware of a letter dated October 3, 2019 which was purportedly written to the office of the Whistleblower Protection Program, Washington DC. This letter refers to the September 20, 2019 complaint, and to emails and voice recordings in support of the allegations. The matter was also discussed by the board on October 11.While an external legal team has been appointed to conduct an independent investigation, people aware of the development have told CNBC-TV18 that the audit committee is swiftly taking its own investigation forward.The audit committee is currently in the process of collating the necessary legal and financial documents to aid in the investigation. "The copy of the emails and recordings have not been sent directly to the Infosys board or audit committee," said a person, requesting anonymity. "So Infosys has to work doubly hard to corroborate the evidence, which is the phone recordings and email copies. However that is the first step. To verify all the data presented by the whistleblower and then collate legal financial and other supporting documents on the subject," he added.>> Here’s everything that we know about the Infosys whistleblower complaint and its potential impactIt's after the documents and data points are verified and collated that the committee will move to the next step of investigating personnel.Former Infosys deputy CFO, Sanghrajka resigned from the company after an 11-year stint, on the of October 14, three days after the company announced its second quarter results. The whistleblower complaints were discussed in the October 11 board meeting."Considering how closely Sanghrajka was attached to the company in the timeline for when the allegations were made, the committee believes he would have firsthand knowledge to the operations," said the person. "Same goes for MD Ranganath who was a key part of the company. They can assist in the investigation."Ranganath resigned from Infosys in August 2018 after a seven-year stint."If there were clear instances of corporate governance lapses, MD Ranganath would, if not confirm, be able to assist in the investigation," the person added.But it's not just the two senior most former employees, people aware of the development said that since the allegations are pertaining to the finance team, current employees of the finance and accounting department as well as former executives of finance team that who left Infosys after April 2017 may be brought in as well."The idea is to be thorough in the investigation. When a company does an investigation, the participation of employees and former as well as current executives is voluntary", added a second person with knowledge of the matter.When contacted a Infosys spokesperson said: "We will not be able to comment on the below, other than the statement already issued."