Songka

[ song-kah ]
/ ˈsɒŋˈkɑ /

noun

a river in SE Asia, flowing SE from SW China through Indochina to the Gulf of Tonkin. 500 miles (800 km) long.
Also Yuan Jiang [Chinese yyahn jyahng] /Chinese ˈyüɑn ˈdʒyɑŋ/.
Also called Red River.