Talks between Hamas and Fatah on forming a Palestinian unity government have failed, Fatah officials reported Friday. Among the terms of the proposal was that Hamas would keep most ministerial posts according to its parliamentary majority. Fatah would retain the post of prime minister. Palestinian Authority Chairman Mahmoud Abbas said Thursday that all Palestinian armed groups had agreed in principle to halt Kassam rocket attacks on Israel. "All the factions agreed to maintain calm and stop operations that can be used as an excuse to attack us," Abbas said. The chairman added that Islamic Jihad refused to sign on officially, but agreed to refrain from attacks as long as the other terrorist groups did so. Israeli security forces killed two armed Jihad operatives near Bethlehem Thursday morning.