In 2011, two Chinese cargo ships refused to pay protection money to a drug-trafficking gang on the Mekong River.
Naw Kham, the leader of the gang, swore to take revenge.
On Oct 5, the Hua Ping and Yu Xing 8, which had refused to pay for protection, were attacked and 13 Chinese fishermen aboard were murdered. Their bodies were found floating on the river, with the eyes and mouths covered with black tape and the hands bound.
According to the Ministry of Public Security, between 2008 and 2011, the gang launched 28 attacks against Chinese cargo ships on the river, killing 16 citizens and injuring three.
The gang was busted in early 2012 amid a joint law enforcement operation by police from China, Laos, Myanmar and Thailand.
In November 2012, a court in Yunnan province sentenced Naw Kham and three of his subordinates to death for the murders of the 13 Chinese sailors.
In February 2013, Naw Kham and the accomplices, identified as Hsang Kham, Yi Lai and Zha Xika, were executed by lethal injection in Kunming, Yunnan, according to Kunming Intermediate People's Court.