GAZA CITY, Gaza Strip – Tens of thousands of Palestinians in the Hamas-ruled Gaza Strip demonstrated Tuesday against the Middle East peace conference in the United States, while the Islamic militant group’s leader insisted it was “doomed to failure.”

In the West Bank city of Hebron, Palestinian police loyal to President Mahmoud Abbas violently dispersed a demonstration against the peace conference, killing one protester, medical officials said.

Abbas is attending the Annapolis, Md., conference and protesters filling a huge square in Gaza City called him a “collaborator” for participating and chanted “Death to America” and “Death to Israel.”

Ismail Haniyeh, leader of the Hamas government in Gaza, expressed dismay over the participation of 16 Arab nations at the United States summit. They included Saudi Arabia and Syria, a key Hamas patron.

The Arab masses “will reject … any concessions to the Zionist enemy,” Haniyeh said. “We are sure that the Annapolis conference will not change the reality of history and geography,” he added. “Any conference that goes beyond this reality is doomed to failure.”

The rival government of Abbas in the West Bank banned protests against the peace conference to preserve “stability and security.”

Enforcing the ban, police broke up small demonstrations throughout the Palestinian territory.

The Liberation Party, a tiny Islamic group, said Hisham Baradiyeh, a 36-year-old member, was shot in the chest. The group calls for the establishment of a pan-Muslim state through peaceful means.

Several people were seriously injured, medical officials said.

Palestinian Cabinet minister Ashraf Ajrami said there was a “plot to harm the standing” of Abbas’ government while he is in the international limelight. He said the government “must investigate the events surrounding the incident” in which the protester died.

In other violence, Israeli troops fatally shot two Hamas militants in separate incidents early Tuesday in Gaza, the army and Islamic group said.

“Annapolis is a disaster for us,” said Amina Hasanat, a 37-year-old mother of eight who demonstrated in Gaza City. Dressed in a black robe and black and green headband, she predicted the conference would end in failure. “This will be an advantage for the resistance,” she said.

Gaza’s Hamas rulers have been staging daily demonstrations against the conference, restating their commitment to Israel’s destruction and promising to reject any decisions that come out of Annapolis. The criticism has grown increasingly vitriolic, with one Hamas leader on Monday calling Abbas a “traitor.”

Polls show a majority of both Palestinians and Israelis favor a negotiated settlement to the conflict. However, a majority on each side is also skeptical that the current peace push will bear fruit.

Hamas violently seized control of Gaza in June after routing forces loyal to Abbas, and his lack of control of Gaza has raised questions about his ability to carry out a future peace deal. Israeli Prime Minister Ehud Olmert has said he will not implement a peace agreement without a halt to militant attacks from Gaza.

Speaking to reporters Monday, Olmert said the United States-backed “road map” peace plan calls on the Palestinians to disarm militants.

But Haniyeh insisted Hamas would not disarm.

“We will stand firmly in the face of policies that attack the will of our people, our factions and our weapons of resistance,” Haniyeh said. “We reaffirm the legitimacy of resistance and support it as a natural right.”

After Haniyeh’s speech, the Gaza protest gained strength, beginning with several thousand pro-Hamas university students and quickly swelling to tens of thousands of people. Smaller militant groups, including Islamic Jihad, also took part.

“Today you are here to send a message to those who say the land of Palestine is not for sale,” said Mahmoud Zahar, a fiery Hamas leader. “Whoever thinks we will recognize a Jewish state … are deluding themselves. There will be no recognition of the state of Israel.”

Despite the harsh language, the gathering was more subdued than past Hamas rallies. Many demonstrators milled about and appeared uninterested during the speeches. Children played or enjoyed ice cream, and women chatted. Unlike other Hamas rallies, there were no public displays of weapons, although protest organizers tried to energize the crowd by playing recordings of gunfire.

In Ramallah, about 1,000 supporters tried to march from a mosque in the town’s center, but were dispersed quickly.