KUNMING - China, Laos, Myanmar and Thailand began?a new round of joint patrols on the Mekong River in the Golden Triangle Region on Friday, to secure transportation and target cross-border crimes, according to Chinese police authorities.

The six-day police patrols, the sixth round of their kind since last December, coincided with the ongoing trial in Southwest China's Yunnan province of six suspects who were allegedly involved in an attack last year on the southeast Asian watercourse that left 13 Chinese sailors dead.

The patrol fleet of China and Laos will sail along a Laos-managed section of the Mekong River to check ships, said a police officer in charge of China's Yunnan Provincial Border Control Corps.

Police officers will also check key sections on the bank of the river in Laos, added the source, who declined to be named.

Chinese shipping on the river was seriously affected after two Chinese ships were attacked and hijacked in October last year. The joint patrols, considered a safeguard against crimes on the river, have seen more ships resume operation.

Statistics showed that only 10 Chinese ships were shipping on the river when the first four-country joint patrol was launched in December last year. That number increased to 59 when the fifth patrol was conducted in August.