Nanjing is a city where Chinese people have bitter war memories.

Japanese troops occupied Nanjing on Dec. 13, 1937, and launched a six-week massacre. Chinese records show more than 300,000 people, including disarmed soldiers and civilians, were killed.

This year marks the 65th anniversary of Japan's surrender in WWII.

Under the Chemical Weapons Convention which came into effect in 1997, all states that possess chemical weapons must destroy them by April 29, 2012.

HIDDEN DANGER

Japanese troops developed and produced a great number of chemical weapons during their invasion of China. They buried or abandoned many of these weapons to cover up their crimes before they surrendered.

These abandoned chemical weapons are often discovered in different places across China, mostly in China's northeastern regions.

On Aug. 4, 2003, a mustard gas leak from chemical weapons abandoned by the Japanese troops killed a man and injured more than 40 in Qiqihar in northeast China's Heilongjiang Province.

In August this year, police found more than 400 abandoned Japanese bombs within half a month at construction sites and abandoned factories in Qiqihar.

"The city was once the headquarters of two chemical weapons units of Japanese troops during WWII," said Zhang Ronghui, deputy director of the Qiqihar Public Security Bureau.

"Now, it is a heavy burden for local governments to properly dispose of those abandoned chemical weapons," he said.

Local residents hope the Japanese government can inform of the exact number of chemical weapons buried underground.

"How many? Where are they? I hope Japanese government, together with Chinese side, can give us a clear answer to these questions to reduce the number of casualties," said Mei Hanjue, a Qiqihar resident.

Chinese scholars expressed appreciation for Japan's move Wednesday.

"It shows the positive attitude the Japanese government has in handling the issue of abandoned chemical weapons, and this should be recognized," said Gao Hong, deputy director of the Japan Studies Institute at the Chinese Academy of Social Sciences.

The abandoned chemical weapons issue not only injures and kills Chinese citizens but also hurts their feelings, and furthermore, affects China-Japan relations, Gao said.

"The Japanese government's move to destroy the abandoned weapons can also be seen as an important step in Japan's reflection on its war past," he said.

But he warned the cost of destroying the weapons will be even high, saying China needs to see what the Japanese government will do next.

In addition, there is still another issue: compensation.

"The Japanese government's move is an important step in handling the issue of abandoned chemical weapons. But the issue of compensation for Chinese citizens injured or killed by those weapons should also be addressed," said Liu Zhiwei, a lawyer at the Heilongjiang Langxin Law Firm.