China's biggest port, Dalian, was shut on Monday in response to a pipeline explosion that sent thousands of tons of crude gushing into the Yellow Sea and closed major businesses, Press TV reported.
The explosion occurred in the port in northeastern China on Friday when a crude oil tanker was being off-loaded.
About 1500 tons of crude oil has poured into the sea, causing a 182-square-kilometer oil slick.
In the wake of the incident, two strategic refineries, the Dalian Petrochemical Corp and WEPEC, which together process 600,000 barrels per day, stopped their operations, Reuters reported.
In addition, cargo shipments, including oil, iron ore, and soy, have been disrupted.
So far, 20 kilometers of the oil slick has been cleaned up and 160 tons of crude has been collected, officials say.
According to the local government, the clean-up process may take five days. No timeframe, however, has been given for reopening the port.
Officials of Dalian Port, whose shares dropped 5 percent following the incident, say no one was hurt during the incident and the main terminal facilities have not been damaged directly.
Environmental activists have pointed to the incident as another sign of China's laxity toward the ecosystem and called on the country to adopt tighter environmental standards.