Chinese auditors will launch an investigation into the country's five largest telecommunications operators from early October, the National Audit Office (NAO) has announced.

Special audit teams will scrutinize China Mobile, China Telecom, China Unicom, China Netcom and China Railcom to see whether they comply with the country's financial and economic laws.

The investigation, which will last for two months as part of an NAO plan mapped out earlier this year, aims to encourage these state-owned firms to improve management, raise economic returns and sharpen their competitive edge, said the NAO.

Last year four of the five firms - excluding China Railcom - reaped combined profits of 104.73 billion yuan (US$13.96 billion), about 14 percent of the total made by the 159 central state-owned enterprises.

(Xinhua News Agency September 27, 2007)