By Nidal al-Mughrabi
GAZA, June 15 (Reuters) - Western-backed President Mahmoud Abbas dismissed the Hamas-led Palestinian government and declared a state of emergency as the Islamist group's gunmen routed his last forces in Gaza and seized effective control.
While Washington rallied support for Abbas, Hamas stormed remaining strongholds of his secular Fatah group in the Gaza Strip on Thursday, finally seizing the presidential compound, the last bastion of Abbas's authority in the coastal territory.
Jubilant Hamas gunmen hunted Fatah loyalists, killing some and parading one top figure's mutilated body through the streets. "Allahu akbar! (God is Greatest!)," one gunman chanted through a megaphone from a captured Fatah security headquarters.
Medics said at least 30 people were killed on Thursday, taking the death toll to more than 110 in six days of conflict which leaves an aggressive Islamist entity on Israel's borders.
Abbas, from his power base in the West Bank, accused Hamas of staging a coup in Gaza in the fighting, which has ripped apart international proposals for Middle East peace that envisaged Gaza and the West Bank as a future Palestinian state.
Prime Minister Ismail Haniyeh, a senior leader of Hamas which enjoys support from Iran and Syria, said his government would ignore Abbas's "hasty decision" to dismiss it. Haniyeh blamed Fatah for pushing the Islamists to react.
Fatah and Hamas had gone into government power-sharing deals in an effort to overcome their differences but these were plagued by violence between their supporters.
In a statement, Abbas said he was "declaring a state of emergency in all the lands of the Palestinian Authority because of the criminal war in the Gaza Strip ... and military coup".
Abbas, successor to the late Yasser Arafat who embraced negotiation with Israel to try to found a Palestinian state in the two territories, said he would form an emergency cabinet to rule by decree and held out the prospect of early elections.
But gun law, not the constitution, held sway in Gaza.
Cheering Hamas fighters hoisted green Islamist flags over Fatah buildings. The fate of Fatah fighters seen being led away, bare-chested, after surrendering was unclear. There were unconfirmed reports of prisoners being shot.
The White House accused Hamas of "acts of terror" and U.S. Secretary of State Condoleezza Rice called Abbas to emphasise support for Palestinian "moderates" but acknowledged finding troops for any international force for Gaza would be tough.
CRIPPLING EMBARGO
Some of Gaza's impoverished 1.5 million people view with trepidation the success of Islamists set on defying a crippling Israeli and Western embargo. But Hamas has many supporters.
Nailing Washington's colours to Fatah's mast, a tactic some say hurts Abbas's position with his own people, Rice said: "President Abbas has exercised his lawful authority ... We fully support him."
Analysts believe such talk may signal an easing of year-old anti-Hamas sanctions on the West Bank to bolster Abbas. The sanctions were introduced after Hamas won a majority in parliament at elections in January last year.
A Fatah official in Gaza said he had seen eight colleagues gunned down while he escaped death "by a miracle".
Hamas's armed wing said it "executed" Samih al-Madhoun of Fatah's al-Aqsa Martyrs Brigades, an ally of Abbas security aide Mohammad Dahlan. His body was dragged through a refugee camp.
Some Fatah gunmen retaliated against Hamas in the West Bank, seizing Hamas supporters in the towns of Jenin and in Nablus. The Brigades said its men killed a Hamas supporter in Nablus.
Businesses owned by Hamas supporters were targeted by angry crowds in the Israeli occupied territory, where some 2.5 million Palestinians live.
Haniyeh, who unlike Abbas spoke in person on television, blamed Fatah for abusing its power and persecuting Islamists. "They pushed people into reacting," he said.
But he called for restraint from his fighters and offered talks: "I call for a national and comprehensive dialogue to begin immediately."
For Hamas fighters in Gaza, some in camouflage uniforms, the fall of one Fatah base after another was cause for celebration. They fired in the air and handed out sweets.
Others paraded in the streets and showed off weaponry seized from Fatah, whose forces the United States has helped train and arm in a bid to counter the rise of Hamas -- to little effect.
Diplomats, who declined to be named, said an aide to Abbas had acknowledged hundreds of Fatah's men ran away from battle or ran out of bullets during the fighting. (Additional reporting by Mohammed Assadi and Wafa Amr in Ramallah and Ori Lewis, Allyn Fisher-Ilan, Jeffrey Heller and Alastair Macdonald in Jerusalem)