BEIJING, Jan. 10 (Xinhua) -- Chinese police have taken out 41 criminal gangs in a special campaign on waters of the main channel of the Yangtze River, according to the Ministry of Public Security.

Since the ministry launched the campaign at the beginning of December 2019, 402 criminal cases have been cracked, involving illegal sand mining, fishing and pollution discharge and waste dumping in the waters, the ministry said.

Police have also urged relevant parties to deal with over 600 potential risks after they checked over 5,000 ships and more than 2,000 units and venues involved in water-related work.

They have also carried out joint law enforcement with authorities of fisheries, maritime affairs, water conservancy and ecological environment.

The campaign will last for seven months.