Three people were killed and three others injured in a blast at a chemical plant on Wednesday afternoon in the city of Wenzhou, east China's Zhejiang Province.

Local police said the accident took place around 2:00 PM as workers welded a pipeline of polyurethane, which is combustible. This was confirmed as an illegal operation by experts.

The polyurethane ignited immediately, causing extensive fires and the explosion of two large containers.

Among the?wounded in the accident, one is in a critical condition, said the local hospital.

The fire was put out at around 5:20 PM, and further investigation into the cause of the blast is underway.

(Xinhua News Agency December 30, 2004)