In a campaign against drug crime begun two years ago in the province, police officers investigated a man, Zheng Liang, 41, suspected of distributing drugs.

In March, investigators discovered Zheng, who had disappeared for a time, frequently traveled between Haikou, capital of Hainan, and Guangzhou, capital of neighboring Guangdong Province.

After further investigation, officers found Zheng, with an assistant Gu Dongchun, often went to Guangzhou on drug deals with a man from Xinjiang Uygur Autonomous Region.

In April when criminal investigators followed Zheng and were going to capture him and the Xinjiang man, Zheng discovered he was under surveillance.

He immediately halted the trade. The guy also changed contacts and moved to a new residence and vanished.

In May, Zheng was found dealing drugs with another suspected trafficker Li Gang.

On June 7, police officers captured six suspects, including Zheng, Gu and Li, in a club on Lantian Road in Haikou. Later officers also seized another five suspects and 800 grams of heroin.

On June 10, an undercover investigator pretending to be Zheng's assistant contacted the Xinjiang man Zheng previously traded with.

Undercover investigators, pretending to buy heroin from him, detained the man in a hotel in Guangzhou and seized 600 grams of heroin. Three other suspects were captured later.