About 40 Chinese plan to file a petition with Prime Minister Junichiro Koizumi next month demanding an apology, medical care and life support for injuries they sustained from a toxic gas leak from chemical weapons abandoned in China by the Imperial Japanese Army, according to their lawyers.

If they see that Japan is not addressing their plight adequately after the petition is filed Aug. 4, the group will bring a lawsuit seeking an apology and damages, the lawyers said at a recent news conference in Tokyo.

So far no suit has been lodged by the victims.

Aug. 4 marks the second anniversary of a deadly chemical weapons leak from barrels that were discovered at a construction site. One accidentally broke, killing one local resident and injuring 43 others in the city of Qiqihar in Heilongjang Province.

Japan has paid China 300 million yen in the name of "costs for the disposal of chemical weapons abandoned" in the city after the war.

Seven of the victims, including three children, are scheduled to visit Japan later this month, according to the lawyers.

"Symptoms are worsening for some people, yet medical care provided in China is inadequate," said lawyer Norio Minami. "Some people have not been able to return to work and some children are being bullied."