Naw Kham, the Myanmar drug lord and three of his accomplices will be executed by lethal injection Friday afternoon in Kunming, Yunnan Province, for murdering 13 Chinese sailors on the Mekong River in 2011, a local court said.

The Kunming Intermediate People's Court identified the other men as Hsang Kham from Thailand, Zha Xika from Laos, and Yi Lai, who was described as stateless.

Naw Kham, head of the largest armed drug trafficking gang in the notorious Golden Triangle, was captured last April in Laos after being tracked for half a year by police from China, Myanmar, Laos and Thailand.

The four men were convicted by the Kunming court last September and their appeal was dismissed in November.

Their sentences were approved in late February by the Supreme People's Court, which reviews all death sentences handed down by lower courts. The execution will be supervised by the Kunming People's Procuratorate.

Local judiciary authorities confirmed to the Global Times that after making arrangements with consulate officials from Thailand and Myanmar in Kunming, Yi Lai and Hsang Kham were visited by relatives Thursday morning. No one came to visit Naw Kham.

"Since Naw Kham was informed of his execution date on February 24, he has been emotionally unstable and has been pleading for forgiveness," a judiciary officer said.

The men's personal belongings will be transferred to their family members.

Other accomplices include Zha Bo, who was previously sentenced to death with reprieve and Zha Tuobo, who received an eight-year prison sentence.

Two Chinese boats, Yuxing 8 and Huaping, were hijacked by the gang to transport some 80 kilograms of methamphetamine after 13 sailors onboard were abducted on the morning of October 5, 2011, according to police investigation.

Authorities in Thailand are still investigating whether some of their soldiers were involved in the killing. At the men's trial the Chinese court heard that soldiers colluded with the gang and shot the sailors.

Liu Yuejin, head of the anti-drug bureau under the Ministry of Public Security, told the Global Times earlier that they had considered using a drone aircraft to attack Naw Kham and his fleeing gang members in Myanmar. "But the plan was put off as we wanted to capture the drug lord alive."