The Israeli army has engaged Palestinians in the West Bank and the Gaza Strip since Saturday, killing at least nine. Hamas immediately retaliated Sunday, urging militants to arm up against the Jewish sate.?

Palestinian observers viewed the Israeli intervention as "a sudden escalation that Israel wants to make future political achievements or escape from commitments to resume the stalled peace process."

On Sunday afternoon, a 16-year-old boy was killed near the village of Aabood, west of Ramallah, on the second day of an Israeli offensive that left eight others dead.

Medics at Ramallah Hospital said that Kareem Zahran died from a shot to the chest during clashes opposing students and the Israeli army.

Earlier in the morning, the Israeli army killed two Fatah militants in Nablus city.

On Saturday evening, a bystander died during an Israeli air raid aimed at a car carrying militants in the northern Gaza Strip. Five others were shot dead in the West Bank, including a 17-year-old girl.

The sudden surge of violence could topple a ceasefire that has lasted six months in Gaza. Israel scoffs at this claim, saying over 150 rockets have been launched from Gaza into Israel since November when the ceasefire began.

Following the escalation of Israeli operations, Hamas immediately made a call to arms Sunday, urging militants to prepare for reprisals against the Jewish sate.?

In a statement sent to reporters, Hamas spokesman Fawzi Barhoom called on the militant factions "to unite and use all means of resistance to respond to the massacres committed by the Israeli occupation."

Hamas further demanded Abbas halt any meetings with Israeli officials, including his bi-weekly meetings with Israeli Prime Minister Ehud Olmert.

The oft-divided Hamas and Fatah parties seemed to find accord when a militant leader of Fatah's armed wing in Nablus said, "We don't relay on Abbas-Olmert meetings because they are often followed by assassinations."

Jamal Nazzal, the official spokesman of Fatah, called for calm and asked the militants to keep the peace "in order to block the new Israeli policy that aims at programming the Palestinian reactions according to the times Israel selects."

Nazzal called the Israeli escalation an attempt to ridicule the new power-sharing deal between the Palestinian rivals "and so the international siege remains in effect."

Mustafa al-Barghouti, spokesman for the Palestinian government, slammed the Israeli operations as "a planned military response to Palestinian initiatives seeking to extend the ceasefire to the West Bank."

"The Israeli government is crippled and tries to hide its failure by resorting to military means," said al-Barghouti. Political analyst Hani al-Masri said the Israeli government sought "to keep up the aggression and its policy of making up facts to make its version of effects more palatable."

(Xinhua News Agency April 23, 2007)