Cultural heritage experts Wednesday hailed a move to protect buildings dating from the Manchukuo era, a puppet state established by the Japanese invaders in Jilin Province, as a necessary step for Chinese people to better understand a key period in the nation's history. 

Eleven modern historical relics and buildings were listed as key national cultural relic protection units by the State Administration of Cultural Heritage, according to a notice published on Friday.

Most of the sites dated from the Manchukuo period, but some are also historic industrial sites not built by the Japanese, said Jin Xudong, head of Jilin Provincial Cultural Heritage Bureau in Changchun, the Xinhua News Agency reported Wednesday.

The Manchukuo buildings include those used for military or political purposes, such as the Manchukuo Imperial Palace. These have a typical colonial style and represent the highest level of Asian architecture from that time, Xinhua reported.

The region of Manchukuo included Northeast China, eastern Inner Mongolia and Chengde in Hebei Province. In 1931, the region was seized by Japan following the September 18 Incident, and in 1932, a puppet government was created, with Puyi, the last Qing Dynasty (1644-1911) emperor as its figurehead.  

Although the history of Manchukuo is short, preserving its buildings is important to better understand the history of Japan's invasion of China, Qu Xiaofan, a professor at the School of History and Culture at Northeast Normal University in Changchun, said Wednesday.

"A civilized city should retain good buildings from every historical period. However, in past years, people have their own political judgment when they mention cultural relics. People usually tear down historic buildings that bring unpleasant memories," Qu said.

In 1995, the South Korean government demolished a government house built by Japanese invaders in 1926 in Seoul, according to people.com.cn.

In 2010, several buildings built by the Japanese invaders between 1920s and 1940s were demolished in Dalian, Liaoning Province, which stirred heated disputes, according to the China Youth Daily.

Some Chinese Web users in recent years called on people to follow South Korea's example and demolish buildings left by foreign invaders in China, a notion experts think is very dangerous.

"A nation should face the tough years in its history. If it's invaded, enslaved and bullied by others, it should not hide that history but should demonstrate it to the world and let its descendents remember that forever," said Zhou Xueying, a history  professor from Nanjing University.