The terrorists, mostly Syrians, were killed when warplanes bombed their weapon chases in al Raqqah.
It is not clear whether the airstrikes were launched by the Russian or the Syrian forces.
The London-based observatory said that five al Nusra Front militants were killed by a drone in Idlib.
The SOHR added that 143 killed on Tuesday, including 36 pro-Assad forces and 36 civilians.
Source : MENA