Twelve more bodies have been recovered from the Queiq River in Syria's Aleppo city a day after 22 corpses were pulled out.
Corpses have been appearing on the river shores since late January when at least 80 bodies were found, many with bullet wounds to the head.
The opposition says government forces are responsible for dumping the bodies in what has become known as the River of Martyrs.
Most bodies found so far floated down to the opposition-held Bustan al-Qasr neighbourhood after being dumped in an upstream district in central Aleppo under government control where several security compounds are located, opposition activists in Aleppo said.
State media said the bodies found in January were those of people abducted and killed by the rebel group Jabhat al-Nusra.
President Bashar al-Assad's forces and rebel brigades have been battling in Aleppo, formerly Syria's commercial and industrial hub, since last year.
Both sides have been accused of carrying out summary executions.