TOKYO - Japan and China on Thursday agreed to set up a joint group to clear an estimated 660,000 chemical weapons abandoned in China by Japan's Imperial Army at the end of World War II.

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The agreement, which came during talks between officials of the two countries in Tokyo, is part of an ongoing project to remove weapons from around the Chinese city of Dunhua in northeastern Jilin province.

Japan will dispatch about 50 consultants to the organization to speed up excavation of weapons from the area, according to Hisashi Michigami of the Foreign Ministry, who briefed reporters following the talks.

Chinese officials said they viewed Japan's efforts positively, but demanded that excavation be speeded up, according to Michigami.

Japan has spent 93 billion yen (US$787 million) removing 38,000 chemical weapons in the area, but the arms are stored in Chinese warehouses and have yet to be disposed of, Michigami said. The disposal costs are expected to top those incurred removing them, he added.

Chinese Foreign Ministry spokesman Qin Gang blasted Japan's use and subsequent handling of the chemical weapons.

"It is a heinous crime committed by Japanese militants in the past ... a major leftover issue of history between the two countries, and a major threat to the life of people in relevant regions," Qin said in Beijing.

"We hope that Japan can abide by its commitment to solve this issue earnestly and at an early date," he said.

Japan occupied China's northeast, also known as Manchuria, from 1933 until its wartime defeat in 1945. The retreating Japanese army left an estimated 700,000 shells with mustard gas and other poisons, almost half of which likely remain in the Jilin area, according to a Japanese government estimate.

Beijing has said abandoned chemical weapons have killed at least 2,000 people in China since 1945.

A 1997 international convention required Japan to remove the weapons by April 2007. But Japan and China requested an extension until 2012 because of the large number of weapons still to be unearthed.

Japanese officials have said Japan wants to make preparations to build a chemical weapons disposal factory in Jilin by the end of March, pending China's approval.