China will next month launch joint patrols with three other countries on the Mekong River, a key waterway where 13 Chinese sailors were killed in an October attack, state media said.

The patrols, which official media has previously said would be armed, will begin by December 15, the state Xinhua news agency said late Saturday.

Chinese police will join forces from Laos, Myanmar and Thailand to restore shipping and guarantee security, it said, quoting China's Ministry of Public Security following a meeting of the four countries.

The sailors died in a raid on two Chinese cargo boats on the Mekong on October 5 -- an attack thought to have been carried out by a notorious gang in the "Golden Triangle" area known for drug smuggling.

Police in Thailand have since detained nine soldiers suspected of killing the sailors, and also thought to have links to a Myanmar drug kingpin.

The Mekong flows through China's southwestern province of Yunnan into Southeast Asia, serving as a major trade route through several countries including Cambodia and Vietnam.

China reacted angrily to the October attack, summoning diplomatic envoys from Thailand, Laos and Myanmar and asking authorities to speed up investigations into the incident.

Beijing has taken the lead in the initiative to start patrols and Xinhua said China would set up a headquarters for the effort, able to communicate with offices in the other three countries on a 24-hour basis.

Police in the four countries would explore more ways to improve security on the waterway, and China will help train and equip police in Laos and Myanmar for the patrols, the report said.

After the October attack, China sent patrol boats down the Mekong to escort 164 stranded Chinese sailors and 28 cargo ships home.