Militants challenged Yasser Arafat's authority once again Monday as they raided Gaza City's largest hospital in broad daylight and killed two men convicted of collaborating with Israeli intelligence.

Gunmen participating in a funeral for three militants killed in overnight battles with Israeli forces broke away from the procession and stormed Shifa hospital, where they entered the room where Mahmoud al-Sharef, 52, was being treated. They shot al-Sharef twice in the head and escaped. One militant was detained by police for questioning.

Five hours later, another group of at least 20 militants raced up in several vehicles to the hospital's front entrance. Five entered the intensive care unit, where they found Walid Hamdiyeh, 42, being treated. They shot him three times in the head and chest, killing him.

The two men were admitted to the hospital with wounds suffered earlier in a previous attack, when a grenade exploded in their jail cell.

The two had confessed to the charges during their trials. Although those suspected of collaborating with Israel are often killed, observers say the most recent attacks -- carried out in military-style daylights raids, in full view of of hundreds of witnesses -- underscore a degeneration into lawlessness in the territories controlled by the Palestinian Authority.

The militant group Hamas claimed responsibility for both the initial grenade attack and the deadly hospital raids.

On the weekend, militants in the West Bank city of Jenin poured into the streets carrying posters of Arafat only a day after they had torched government buildings to protest corruption within the Palestinian Authority.

The rise in anti-Arafat sentiment has sparked criticism from Palestinians, who say the violence and kidnappings are damaging how the world sees them. The parades were the latest declaration of  allegiance to Arafat, president of the Palestinian Authority, to counter demonstrations against him and his officials.

Crowds also flooded the dusty streets of Ramallah to rally support for their embattled leader. The crowd cheered along to a marching bands and militants on parade to give proof that Arafat is still their leader and indisputable symbol of Palestinian ambition.

Zakariyeh Zbeideh, leader of the Al-Aqsa Martyrs Brigade in Jenin, called upon Palestinians to support Arafat in spite of growing frustration over cronyism and corruption.

"While we are fighting our enemy, we cannot talk about it," Zbeideh said to a crowd of supporters. At the same time in Nablus, gunmen loyal to Arafat disrupted a meeting to push for reforms in his party.

Palestinian Prime Minister Ahmed Qureia has also tried to show his commitment by appearing with Arafat, in spite rumours of a rift between the two men. Arafat also vowed to stand firm against what he calls conspiracies, to brand him a man of the past and not one of the people.

Israeli forces demolish camp buildings

Also Monday, one Palestinian woman was killed as Israeli forces entered the Khan Younis refugee camp in Gaza and opened fire before demolishing six buildings. The Israeli military said the woman was killed when a bullet went through her window. The military said that helicopters fired warning shots to keep militants away from the area.

The Israeli military also said the area was used by Palestinians to attack a nearby Jewish settlement with mortar and rifle fire.

With a report from CTV's Janis Mackey Frayer and files from the Associated Press