The number of illegal immigrants in the United States was estimated to stand at over ten-point-seven million last year, including 200-thousand South Koreans.

The Ministry of Land, Transport and Maritime Affairs said on its Web site Thursday that some 200-thousand South Koreans are illegally residing in the U.S., accounting for around two percent of all illegal aliens in the U.S. The figure was sharply lower than the 240-thousand posted in 2008.

Mexicans topped the list of the largest group of illegal immigrants in the U.S. with about six-point-six million. Illegal aliens from El Salvador came second followed by immigrants from Guatemala.

The total population of illegal aliens in the U.S. for last year dropped by 850-thousand compared to 2008 following the U.S. crackdown on illegal immigration amid the financial crisis.