National Stock Exchange said on Wednesday it will remove Satyam Computer Services Ltd from its S&P CNX Nifty 50-share index from January 12.

The head of the outsourcing firm resigned on Wednesday, disclosing profits had been falsely inflated for years, sending its shares crashing nearly 80 per cent.

The exchange did not give any reason for the change. Anil Ambani-group firm Reliance Capital Ltd will replace Satyam in the main index, the exchange said in a statement.

Satyam will also be excluded from the CNX 100 index, CNX 500 index and the CNX IT index. Satyam is a component of the Bombay Stock Exchange's main 30-share index, the country's benchmark index.