BEIJING, July 7 -- China commemorated the 78th anniversary of the start of its eight-year resistance against Japanese invasion on Tuesday, underlining the country's essential role in World War II.

Activities were held nationwide to mark the "July 7 Incident" of 1937, when Japanese troops attacked Lugou Bridge, a crucial access point to Beijing.

Japan invaded northeast China in September 1931, but historians generally agree that the July 7 Incident marked Japan's full-scale invasion and the start of China's eight-year war of resistance.

COMMEMORATIONS

East China's Shandong Province on Tuesday launched an online memorial explaining the history of the anti-Japanese war through 3D video.

The online museum offers stories and information about battles that happened in Shandong during the war. It also displays the names of soldiers and civilians who died during the war.

Wang Junmin, vice party chief of the province, said people can access the museum through computers and cell phones, and the content is available in different languages, including Chinese, English, Japanese and Korean.

The privately run Jianchuan Museum in Anren Township of Dayi County in Sichuan Province opened an exhibition hall on Tuesday, showing more than 6,000 items documenting Japanese atrocities during WWII.

The 3,500-square-meter exhibition hall was designed by Japanese architect Arata Isozaki. About 95 percent of the items are from Japan, said museum owner Fan Jianchuan.

The items include records of Japanese killing Chinese civilians, letters from Japanese soldiers, official documents on bombings, propaganda pictorials boasting of military achievements, shell debris and Japanese officers' swords.

"I hope this exhibition can attract large numbers of Japanese people to visit and reflect," said Fan.

The government of Jiangsu Province on Tuesday launched a photo exhibition in the provincial capital of Nanjing. More than 700 historical photos depicting Japanese soldiers' cruelty and Chinese people's resistance were displayed.

Among the visitors was 90-year-old Li Jianfeng, once a soldier in the anti-Japanese war. Li said the pictures have recorded much of the history and are of great value. "Knowing history can help us better recognize our responsibilities and do better in our work," he said.

In Beijing, two monuments were launched on Monday in memory of Tong Linge and Zhao Dengyu, commanders of the Nationalist Army who sacrificed their lives during the anti-Japanese war.

Early on Tuesday, Wang Lei left his home in the southern suburbs of Beijing and arrived at the sculpture of Zhao Dengyu in downtown Beijing after an hour-long bicycle ride.

"It is a special day today. I just want to come here to have a look at the sculpture, get to know the stories of the heroes, and feel their spirit in my heart."

CHINA'S ESSENTIAL ROLE

In his book "Forgotten Ally, China's World War II, 1937-1945," Rana Mitter, a professor of history at Oxford University, tells how the Chinese people played an essential role in the wider war effort and made great sacrifices.

According to Mitter, China's persistent resistance was of great importance for the allies in fighting fascist forces and winning victories in Europe and Asia during WWII.

In the anti-Japanese war, the Communist Party of China (CPC) worked toward establishing a national united front of resistance against Japanese troops and an international joint anti-fascist front.

The CPC also mobilized the masses behind enemy lines to participate in the resistance. The CPC-led army and civilians killed 1.7 million Japanese troops and puppet forces during the war.

More than 35 million Chinese were killed or injured in the anti-Japanese war, accounting for one-third of the total casualties of all countries during WWII, according to incomplete official statistics. In the Nanjing Massacre of December 1937 alone, Japanese troops slaughtered at least 300,000 Chinese.

Chinese troops killed, wounded or captured more than 1.5 million Japanese soldiers, accounting for 70 percent of casualties of Japanese forces.

The war also caused more than 100 billion U.S. dollars in direct economic losses for China.

The main force of the Japanese army was in China during WWII, said Tan Huwa, a researcher with Yan'an University in Yan'an, a revolutionary base in northwest China's Shaanxi Province.

China's fierce resistance prevented Japan from attacking the Soviet Union or sending more forces to the Pacific battlefield, disrupting Japan's war plan, he said.

This year marks the 70 anniversary of the end of WWII. Japan signed its formal surrender on Sept. 2, 1945, and China celebrated its victory the following day.

China will hold a military parade on Sept. 3 at Beijing's Tian'anmen Square to commemorate the great victory.