Hamas security forces in Gaza have arrested more than 100 Fatah supporters after six people were killed in an explosion last night.
An unknown group calling itself the “al-Awda Brigades” says it planted the bombs.
However, Hamas has blamed Fatah militants. Fatah leaders deny any involement.
The only thing which seems clear after the large-scale crackdown is that it has futher reduced the chance of an eventual reconciliation between the warring sides.
Thousands of Hamas loyalists turned out for the funerals of the victims of Friday’s attack.
At least 15 other people were hurt in the explosion near a crowded Gaza City beach.
It was one of three attacks in Gaza, marking one of the biggest flare-ups in internal violence since Hamas seized control of the territory a year ago.