The investigation agency reported that 40 locals took a motorised boat to travel along the Mang River in Loc An commune, Loc Ninh district, to Cambodia to work on October 23.
On the way back in the afternoon, the violent torrents of water caused the old boat to turn upside down about 50m off the Mang River bank.
Thirty-three people clung to tree branches along the river banks, and seven others were swept away.
On October 24, rescue workers found the five dead bodies and are searching for the remaining two missing.
