About 40 vessels have been deployed to lay booms and throw felt cloth onto the water's surface to absorb the oil. Some 7,000 metres of floating booms have been set up and at least 20 oil skimmers were working to clean the spill, the China Daily reported. The authorities have used more than 30 tonnes of chemicals to neutralise the oil.

Environmentalists fear that the government's rescue effort might do more damage and predicted worse developments from the massive spill in the Yellow Sea.

The blast and fire destroyed one oil storage tank with a capacity of 100,000 cubic metres.

More than 2,000 fire fighters and 338 fire engines from 14 nearby cities worked overnight to control flames, which shot 30 metres into the air.

Things could be worse, because the international storage and shipping unit of CNPC has 20 storage tanks that can hold almost 2 million m3 of oil in a special tax zone at the port.

Many are concerned that the oil could pollute popular beaches nearby if the wind changed direction, with serious consequences for the local economy, which relies on tourism.

Media are critical of the situation, noting the lack of proper planning ahead of such a disaster.

Parts of the city of Dalian were still thick with smog two days after the blast. More than 600 households located four kilometres away were evacuated, although local authorities insisted the smoke was not life threatening.

The cause of the incident is being investigated, and experts are trying to reassure the public that the disaster is far less serious than the oil spill in the Gulf of Mexico.

At the same time though, people are wondering about the safety of Chinese industrial plants and the effectiveness of the country’s prevention controls and regulations, given the high frequency of environmental accidents.

Just last week in Fujian, three officials with the Zijin Mining Group, a leading precious metals company, were arrested for the leakage of industrial pollution into a river that killed more than 2,300 tonnes of fish.