More than 8,300 places on the Korean Peninsula have been identified as wartime forced labor sites during Japanese colonial rule, a South Korean commission said Monday.

It is the first time that the number of labor sites on the peninsula has been confirmed by the South Korean government.

A total of 8,329 sites have been found since 2005, compared with 4,119 sites in Japan, the commission affiliated with the prime minister's office said.

The sites can be proof to show Japan's use of the peninsula as a logistics base during wartime.

"According to the law on national mobilization enacted in 1938, Korea served the role of supplying goods, labor forces and money," an official from the commission said. 

The commission said 577 sites were run by Japanese firms that still exist, with Mitsui and Mitsubishi leading the list.

In terms of regions, North Pyongan Province in North Korea had the most with 951 sites, followed by Gyeonggi Province surrounding Seoul with 844, it added.

The forced mobilization was carried out when the Korean Peninsula was a Japanese colony from 1910-45. Many Koreans were conscripted into the Japanese military or drafted to work in the military industrial sector, being deployed in Japan and other countries against their will.

Many of them returned home after the 1945 liberation of Korea, following Japan's defeat in World War II, but others remained. Many are believed to have died during the war.

It is unclear how many people were mobilized for forced labor and then died. Some civic groups claim the number of conscripts is up to a million or more. (Yonhap)