BEIJING - Thai Deputy Prime Minister Kowit Wattana on Monday pledged a fair and just trial against a group of suspects in connection with the killing of 13 Chinese sailors on the Mekong River.

Kowit made the remarks in an interview with Xinhua on the sidelines of a meeting on joint law enforcement on the Mekong River held by China, Laos, Myanmar and Thailand in Beijing.

Kowit said Thai police are analyzing the evidence, while still searching for more clues.

Two Chinese cargo ships, the "Hua Ping" and "Yu Xing 8," were attacked by armed men on the Mekong River on October 5. Thirteen Chinese sailors were killed in the attack in the "Golden Triangle" area -- which overlaps Myanmar, Thailand and Laos.

The suspects, who were servicemen of a task force of the Third Army, reportedly turned themselves in on Friday after the issue of an arrest warrant by police. They have been questioned by police and are facing charges of murder and tampering of evidence.

According to preliminary investigations, the 13 Chinese victims were performing their regular duties on the Mekong River, and weren't involved in any illegal conduct, said Kowit.

He offered his condolences to families of victims and pledged for a fair and just trial.

Laotian Deputy Prime Minister and Minister of Defense Douangchay Phichit, expressed his hope that the four countries would step up law enforcement efforts over the waters under their jurisdiction and cooperate more closely with one another.

Myanmar's interior minister Ko Ko said safety on the Mekong River cannot be achieved single-handedly, and China, Laos, Myanmar and Thailand must work together to achieve the goal.

The Mekong River, known in China as the Lancang River, rises on the Qinghai-Tibet Plateau and flows through China, Myanmar, Laos, Thailand, Cambodia and Vietnam before spilling into the South China Sea.