Hundreds of terrified Gazans fleeing Hamas rule were trapped at a main crossing with Israel on Tuesday, hoping to gain permission to pass through Israeli territory to sanctuary in the West Bank.

Fearing death or persecution, Gazans flocked to the Erez passage after Hamas militants wrested control of the coastal strip from Fatah security forces last week. Israel, which has no interest in letting masses of Gazans pass through its territory and possibly destabilize the quieter West Bank, has refused to let most of them in, saying their lives were not in danger.

By Tuesday, about 600 people were holed up in the long, concrete tunnel that leads to the Israeli side of the crossing. Around 100 people belonged to Fatah security forces, but the rest were civilians, seeking a better life in the West Bank.

Women, children and young men sat between two high concrete walls about 10 yards apart, looking tired and sweaty. Suitcases and trash were strewn on the ground. Some families sat on mats, others on bare concrete. A breeze barely stirred between the walls, and the tunnel, which has no toilets, reeked of urine and sweat.

On Monday, gunmen allied with Hamas disguised themselves as fleeing civilians and hurled hand grenades at Israeli soldiers and Palestinians at Erez, killing a relative of a slain Fatah warlord, and injuring 15 other Palestinians.

In a move to maintain order, Israeli tanks and armored vehicles rolled up to the Palestinian side of Erez on Tuesday, chasing away cars parked next to the tunnel, including vehicles belonging to journalists. One tank parked at the crossing entrance, blocking anyone from entering or leaving the tunnel. Army bulldozers closed the road leading to the terminal with sand, witnesses said.

Two injured men with blood-soaked bandages were among those sleeping on the bare concrete, and one appeared to have been shot.

"We are imprisoned between two walls and they are firing at us from behind," a bearded man in the Erez tunnel told AP Television News. "We're calling on ... all the (Palestinian) authorities to protect these people and children." Like many travelers, he declined to identify himself, fearing for his safety.

Israel, which has sophisticated weapons-screening equipment in place at Erez, said it was only letting the staff of international organizations, people with special permission and humanitarian cases to cross.

"We don't think that all of them there are threatened," Nir Peres, a military liaison officer, told Israel Radio.

"There is a clear conflict between security needs and humanitarian considerations," Peres said. "It's clear that we don't want to see in the West Bank (Fatah-allied) Al Aqsa militants who carried out attacks in the past."

Israel allowed about 50 senior Fatah officials and their families to cross into the West Bank from Gaza over the weekend, citing threats to their safety. Some 200 other Fatah officials are in Egypt, trying to get to the West Bank via Jordan, Fatah officials said.

The situation at the Erez crossing was expected to be one of the first issues new Israeli Defense Minister Ehud Barak will tackle. The former prime minister and military chief of staff was installed as defense minister in a ceremony Tuesday.

Hamas declared a general amnesty for Fatah fighters shortly after it vanquished them in Gaza, but frightened civilians and security officers have not been reassured. Checkpoints have been put up on the road to the crossing to arrest suspects trying to leave, and gunmen inside the crossing have been allowed to fire over their heads, unchecked.

On a Hamas Web site, a deck of cards showing four pictures of Fatah leaders was emblazoned across the home page. "Revenge is coming no matter what," was written under the cards showing former Gaza strongman Mohammed Dahlan, who is exiled in the West Bank, and three other leaders. One photo — of assassinated Samih Madhoun, who was killed by a Hamas mob last week — was crossed out.

Abu Mustafa, a Fatah fighter seeking to leave Gaza through Erez, said he feared he, too, was a marked man.

"They forgave people before, and later killed them. There's no way we'll go back," he said.

Another security officer, who did not give his name for fear of retribution, accused Palestinian President Mahmoud Abbas of not doing enough to bring terrified Gazans into the West Bank.

"We don't want to go back to Haniyeh, and Abu Mazen (Abbas) won't let us in," he said.

Sufian Abu Zaydeh, a former top Fatah official in Gaza, said the Palestinians "need to decide whose lives are really threatened and who doesn't want to be in Gaza and wants to live in a different place."

"There are also those who pose a security risk to Israel and can't enter Israel," he told Israel's Army Radio.

A Fatah leader in the West Bank, speaking on condition of anonymity because of the delicacy of the matter, said Abbas was not interested in having Gazans stream out of the coastal strip and leave it an undiluted Hamas stronghold.

Moshon Vaknin, an Israeli paramedic sent to examine people wounded in Monday's attack at Erez, told the AP that he and his colleagues would set up a field clinic to determine how seriously people were hurt and whether any should be transferred to Israel for medical treatment.

Naim Elian arrived at the passage with the body of his dead infant son just as the shooting began. The 3-month-old boy, Mahmoud, died in an Israeli hospital after heart surgery, and the gunbattle held up his father's sad journey back to Gaza.

"I want to go back so I can bury my son," he told AP Television News.

Hours later he was let into the strip through a separate gate, said Peres, the Israeli military liaison.

Hamas has deployed gunmen along the eight-mile border road separating Egypt from Gaza, and at the Rafah border crossing, to keep people from fleeing into Egypt. Palestinians who tried to leave Gaza via Rafah were turned back at gunpoint.

After the Gaza takeover, Abbas dismantled his Fatah group's coalition government with Hamas and installed a new Cabinet. Hamas has refused to acknowledge the legitimacy of the new government, and insists the old government remains in place.

This rift has in effect left the Palestinians with two governments — one in the West Bank that seeks peace with Israel and the Hamas leadership in Gaza, which is sworn to the Jewish state's destruction.

The Fatah Cabinet met Monday, and the Hamas Cabinet is to meet for the first time since the Gaza takeover later Tuesday, the office of deposed Prime Minister Ismail Haniyeh of Hamas said.

Also Tuesday, Fatah's Central Committee, its top leadership body, decided to cut off all contacts with Hamas, an aide to Abbas said.

Meanwhile, a group of Fatah members have broken away from the movement to form a Gaza-based splinter organization aligned to Hamas, its new leader said Monday.

Khaled Abu Hilal, a Fatah member known for his close relations with Hamas, said he and thousands of other Fatah members decided to form a rival group, called Fatah al-Yasser, with its own military wing, the Higher Military Committee.

Many Fatah members blamed their defeat on their leaders, who they said were weak.