China uncovered 2.85 billion yuan (449.5 million U.S. dollars) of illegal off-the-book funds held by government departments and public institutions in the first 11 months of 2011, the Ministry of Finance announced Tuesday.

Authorities found more than 8,000 "covert coffers," accounts that are often used to embezzle public funds or become a source of bribery, said the ministry in a statement.

From the start of January to the end of November, 2,426 people received administrative penalties for setting up and using such accounts, and 902 were transferred to judicial organs for investigation, according to the statement.

China launched a nationwide operation against "covert coffers" in 2009 as part of its efforts to fight corruption.

The operation has effectively contained such illegal acts but problems still exist in a small number of departments and institutions, said Minister of Finance Xie Xuren.

Xie said in October that the country had unearthed more than 58,000 "covert coffers", involving 26.65 billion yuan, between 2009 and the end of August.