The ninth firing of armor-piercing bullets on Sunday afternoon at a local chemical plant signaled the end of the alarm caused by a chlorine leak and explosion accident in this municipality of southwest China.

Only after upgrading igniting tools from scatter-guns to rockets and finally to the powerful weapon used for attacking military tanks, were all three remaining chlorine gasifiers, or equipment to convert liquid chlorine into gas, detonated successfully at the Tianyuan Chemical Industry Plant.

A chlorine leak was reported Thursday at the chemical plant, and the accident turned into a disaster on Friday afternoon when workers pumped the gas out of chlorine tanks, trying to avoid possible spontaneous explosions.

Instead, five tanks exploded while they were pumping with a machine as a result of a sudden rise of temperature in the tanks.

Experts said the gas should have been discharged through steel pipes under natural air pressure instead of by pumping.

The explosion left nine dead or missing and three injured and forced over 150,000 people to evacuate from the area nearby.

Authorities and experts Saturday decided to explode the three gasifiers by shooting from a distance on Sunday morning to get rid of future possible risks of spontaneous blast.

But the action did not start until noon because of unexpected interruptions.

Two reporters were found to have entered the factory when shooters and the salvage corps were almost ready for the detonation.

Police started a new check to make sure nobody was in the forbidden area, but found some people were working in a private factory.

After the workers were moved out of the area, detonation eventually began.

The first 11 rounds of shooting by scatter-guns and rockets failed to ignite the gasifiers.

While chemical and military experts were considering other alternatives to detonate the gasifiers, evacuees lodged at the No.45 High School were anxiously awaiting the announcement of the end of the alarm, which meant they could return home after spending over 60 hours at the school.

"Though we are well lodged and fed here, I still miss my home and I'm eager to return," said Cheng Chaorong, a worker at the Chongqing Paper Mill whose home is only 500 meters away from the accident site.

After a feasibility study, experts finally decided to use armor-piercing bullets to destroy the gasifiers.

Mayor Wang Hongju and Huang Zhendong, secretary of the municipal committee of the Communist Party of China, were at the detonation scene all day with chemical and military experts.

After nine successive blastings by the powerful weapon, all the gasifiers were exploded and at 5:58 p.m. (Beijing Time), Vice Mayor Zhou Mubing announced that the alarm was ended.

Some 3,000 policemen, 650 armed police soldiers and 160 firemen were involved in the detonation.

Environmental workers kept monitoring the air and water quality throughout the day. Zhang Shaozhi, director with the municipal environmental protection bureau, said that the chlorine content in the air was normal, except for a slight rise during the explosions.

Zhang said the water quality is also favorable for evacuees to return home.

When Cheng Chaorong and other evacuees at the high school were told that they could pack their belongings and prepare to return home, they seemed to be too impatient to wait any longer and rushed to the school ground, waiting for buses sent by the government to pick them up.

About 800 buses were used to sent evacuees home on Sunday evening.

By 9:00 p.m., 30,000 evacuees returned home. Other evacuees who live comparatively farther away from the accident site were sent home Saturday.

It was expected that all evacuated people would return home Sunday night, officials said.

An investigation team on the accident was established, with Vice Mayor Zhou Mubing as team leader. Experts from Beijing also joined the investigation team.

Chongqing witnessed a disastrous gas blow-out at the end of last year and officials involved in the accident had recently received disciplinary punishment.

Ma Fucai, general manager of the China National Petroleum Corp, which governs the blown-out gas field, resigned.

A big fire in northeast China's Jilin city and a stampede in Miyun county of Beijing also led to the resignation of the heads of the local governments.

Source: Xinhua