I suspect you are equally unaware of what the Syrian army is doing in Yarmouk. A suburb of Damascus, once home to 115,000 descendants of Palestinian refugees, now largely depopulated and destroyed.
Quoting from this. Action Group for Palestinians of Syria says at least 3,729 Palestinian refugees have been killed during Syria’s civil war, while 309 are considered missing and another 1,674 are currently detained.
The major killers of Palestinians it seems are other Arabs.