The Competition Commission of India (CCI) has reportedly intensified its antitrust investigation into e-commerce giants Amazon AMZN and Walmart WMT-backed Flipkart, requesting their financial statements.

The Competition Commission of India asked Amazon Seller Services and Flipkart Internet to share financial statements to determine a potential penalty in an ongoing antitrust case, Mint reported, citing two people aware of the development.

The annual revenue details will help determine the penalties in the four-year-old case after hearing the defence of the two firms

The e-commerce giants' financial statements will form the basis for determining the penalty, depending on the outcome of the CCI's hearing of the companies’ defence in the four-year-old case.

The penalty in the case, which has been running for four years, will depend on the outcome of the regulatory hearing. The CCI can impose a charge of as much as 10 per cent of global turnover.