Editor's note: China's national memorial day for the victims of the Nanjing Massacre falls on December 13. CGTN presents a photo series that offers a comprehensive look at the crimes against humanity committed by the Japanese military during its war of aggression against China and the Pacific War in World War II. The series urges reflection on history, appreciation of the hard-won peace and vigilance against any return of Japanese militarism.

The issue of Japan's abandoned chemical weapons (ACWs) in China has once again gained attention, following a recent call by a senior Chinese diplomat for Japan to expedite the disposal process during an international conference.

Wang Daxue, head of the Chinese delegation to the 30th session of the Conference of the States Parties to the Chemical Weapons Convention, said under the Convention, Japan should have completed the destruction of the abandoned chemical weapons by 2007, yet the deadline has been postponed four times, during the Conference of the States Parties of the Organisztion for the Prohibition of Chemical Weapons in The Hague, the Netherlands on November 26.

Wang attributed the delays to Japan's "insufficient attention, inadequate investment, and failure to voluntarily provide meaningful information" about the burial sites of the weapons.

The issue of Japanese ACWs in China is closely tied to Japan's wartime aggression against China, during which Japanese militarists, in blatant violation of international law, deployed a large number of chemical weapons.

A total of 1,791 instances of chemical weapon use have been documented with confirmed dates, locations and casualty records. The resulting casualties exceeded 200,000, according to the white paper titled "China's Arms Control, Disarmament, and Nonproliferation in the New Era," which was issued by China's State Council Information Office in late November.

After its defeat, Japan abandoned a large quantity of chemical weapons in China to cover up its crimes, said the white paper, adding that since the end of World War II, these abandoned chemical weapons resulted in more than 2,000 casualties due to poisoning, gravely endangered the lives and property of the Chinese people as well as the environment.

Up until May 2023, Japanese ACWs have been found in more than 120 locations in 18 provinces, autonomous regions and municipalities directly under the central government in China, according to a report on the implementation of the Chemical Weapons Convention in China released in May, 2023.

As of March 31, 2023, a total of 65,903 items of Japanese ACWs were destroyed, said the report.

Despite the repeated delays in meeting the destruction deadline, the continued presence of Japanese ACWs remains a significant threat to the health and safety of the Chinese people, as well as the ecological environment. This also presents a major challenge to achieving the objectives and goals of the Chemical Weapons Convention.

China requests Japan to make all-out efforts to expedite the disposal process, collect and provide information about the abandoned chemical weapons for the Chinese side in a timely manner, fully assist the Chinese in lead search and identification, and shoulder its responsibility in the treatment of polluted water and soil, said Jiang Bin, spokesperson for China's Ministry of National Defense, at a press conference on December 5.