Fatah
After Hamas won a majority of legislative seats during the 2006 Palestinian elections, tensions between Hamas and Fatah became increasingly violent. In 2007, both parties engaged in a military conflict, in which Hamas won control over the Gaza Strip and forced Fatah into the West Bank. Since the 23-day Israeli assault on Gaza, Hamas has accused Abbas of backing Israel, calling him a traitor and collaborator.
Fatah said 19 of its officials were executed and many more tortured. Gaza residents say Hamas used schools and other public buildings in Gaza City, and the towns of Khan Yunis and Rafah, as detention centers to interrogate members of Fatah. They said three men have been blinded during questioning and over 60 of them shot in the legs as punishment. The Palestinian Center for Human Rights stated that "Hamas operatives killed six members of Fatah" and that " 35 were shot in the knees or beaten.
Reuters reported that Hamas leadership in Gaza "denied the allegations but said authorities had begun tracking down suspected 'collaborators' with Israel."
Read more about this topic: 2009 Hamas Political Violence In Gaza