As many as 29 people in northeastern China were poisoned accidentally by a chemical liquid that was left behind by Japanese invaders during World War II, officials said Friday.

The accident which happened on Monday morning left three people in serious condition.

All the injured are currently being treated at a hospital in Qiqiha'er City, Heilongjiang Province.

The Chinese Foreign Ministry summoned the Japanese ambassador in Beijing to ask his government to take full responsibility for the accident and urged Japan to send officials to the site to solve the problem as soon as possible.

The accident was just the latest in a series of incidents involving chemical weapons leftover by Japanese troops during their occupation of the country from 1937 to 1945.

Chinese experts are currently conducting investigations.

One point they are certain of is that the poisonous oil-like chemical was contained inside five metal containers.

The accident occurred when workers at a real estate construction site in Qiqiha'er unearthed the five metal pots.

Two were already broken but another broke open when they were digging. The chemical liquid spurted onto the clothes of a driver of an excavation machine.

Making matters worse, four of the five containers were sold by workers at the construction site to a local peddler.

The peddler then took the pots to a waste-recycling station at a nearby residential area and cut them open.

The liquid chemicals leaked out further poisoning bystanders, officials said.

Back at the construction site, the liquid-poisoned soil was then trucked away to several other construction sites without any notice, city officials said.

When the number of people who were poisoned surged, the city government called 150 police to close off the construction site.

Another 10 construction sites around the city were closed to stop further spreading of the poison.

(eastday.com August 9, 2003)