A research center focusing on South Manchuria Railway Co. during World War II opened in northeast China's Jilin province Thursday.

The research center, under the Jilin provincial academy of social sciences, will focus on the conduct of the occupying forces in northeast China, especially in terms of economy.

The company was founded in 1906 under the auspices of "economic development." By 1945, when the Japanese surrendered, it was linked to the exploitation of a substantial amount of energy and economic resources.

According to Xue Xueshi, a 90-year-old researcher, the company also collected information for the Japanese Army.

"It was the largest organization formed by the Japanese, and spanned politics, military, economy and culture," he said. "In a way, people from the company were invaders without military uniforms."

After the Japanese pulled out of China, a lot of evidence of their wartime crimes was left by South Manchuria Railway. The Jilin academy of social sciences has 28,000 files of evidence on paper and microfilm.

Jin Yilin, vice head of the Institute of Modern History, said studying South Manchuria Railway could help people understand Chinese society before and during World War II.

During the war of resistance against Japanese aggression, China suffered a total of 35 million military and non-military casualties, accounting for a third of the total casualties of all the countries in WWII.

Starting this spring, Chinese textbooks include the phrase "14-year Chinese People's War of Resistance Against Japanese Aggression," instead of "eight-year," as an official acknowledgment that Japan invaded northeast China on Sept. 18, 1931 as the start of the war.