Environmental group Greenpeace has accused Chinese companies of illegally fishing off the coast of West Africa and taking advantage of weak governance during the Ebola outbreak.
The study finds the number of Chinese fishing boats in African waters hugely increased in the last 20 years and quotes 114 illegal fishing cases in eight years off the coasts of Gambia, Guinea, Guinea-Bissau, Mauritania, Senegal and Sierra Leone.
Greenpeace claims the boats mostly do not have proper licenses and fish in prohibited areas by sending incorrect information "including data that suggested they were in Mexican waters -- or even on land," AFP reported.
According to the report, state owned China National Fisheries Corporation (CNFC) vessels are also involved in the illegal practice.
The study reported 16 illegal fishing cases by Chinese boats in two months in Guinea waters, during the Ebola outbreak which paralysed the governments of West Africa and left them unable to monitor their waters.
The Chinese companies are also accused of under-declaring their fish load to prevent licensing fees and were described as "the worst illegal fishing offenders" in the region, in the report.
Rashid Kang, head of Greenpeace East Asia's China ocean campaign, said "Unless the government reins in this element of rogue companies, they will seriously jeopardise what the Chinese government calls its mutually beneficial partnership with West Africa."
Resources, including fish stocks, are a source of competition for China - which is also clashing with Vietnam and Philippine in the South China Sea.