The country's State Oceanic Administration (SOA) said on Friday that the company "violated the overall development plan in its production at Penglai 19-3 oilfield", Reuters reported.

"Despite obvious signs of accident, the company has not taken necessary precaution measures, causing a major marine pollution accident due to negligence," the SOA statement read.

The company has also failed to meet requirements of an environmental impact assessment report, which lowered its ability in dealing with the emergency, the regulator added.

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