Updated

Egyptian forces and Hamas police exchanged fire across the Gaza-Egypt border Monday, and defiant Hamas leaders warned they would not permit Gaza's resealed frontier to remain closed for long.

A day after Egypt closed Gaza's only gate to the world, one Palestinian was killed and several dozen people were hurt, including eight with gunshot wounds. It was the worst outbreak of violence since Jan. 23, when Hamas militants first toppled the border wall.

The firefight erupted around dusk, and occasional gunshots could still be heard after nightfall.

At about the same time in Gaza City, hundreds of Hamas supporters protested the renewed closure of the border.

"Hamas says today it will not submit to the continuation of the siege, and neither will the Palestinian people," Sami Abu Zuhri, a Hamas leader, told the crowd.

In a challenge to Egypt, Abu Zuhri appealed to Arab public opinion.

"We call on Arabs and Muslims ... to urge their people to rise up and continue supporting the Palestinians until this siege is broken," he said.

Monday's violence and the tough words suggested that Hamas has given up hopes of reaching a deal with Egypt under which the border would reopen with Hamas helping to run it.

The international community and Hamas' main rival, Palestinian President Mahmoud Abbas, reject Hamas involvement at the border, and it appeared unlikely that Egypt would strike a separate deal with Hamas.

On Sunday, Egyptian troops sealed the border with metal spikes and barbed wire, ending a 12-day breach during which hundreds of thousands of Gazans had flooded the Egyptian border area.

Even after the closure, Gazans and Egyptians who found themselves on the wrong side of the frontier were allowed home. However, all border traffic was halted by Egyptian forces Monday.

Witnesses said anger boiled over in the late afternoon as people on both sides waited for permission to cross. Gazans started throwing stones at the Egyptians, and Hamas did not interfere. Only a day earlier, Hamas had helped the Egyptian guards maintain order at the crossing.

After youths began pelting an Egyptian command post in the area, Egyptian forces threw stones back, and then fired tear gas. Medics said 26 people were treated for tear gas inhalation.

At one point, gunfire erupted.

Abu Zuhri and another speaker at the Hamas rally, legislator Ismail Radwan, said Egyptian troops used live fire at the border. Egyptian security officials said the Egyptian officers only fired in the air.

Hamas police denied involvement, but witnesses said they saw Hamas gunmen taking part in the fighting, which left a 42-year-old Palestinian man dead and 44 people wounded.

On the Egyptian side, two officers were wounded by gunfire, eight suffered broken bones from stones and three dozen inhaled tear gas. On the Palestinian side, six Gazans were wounded by gunfire and a dozen were treated for tear gas inhalation, medics said.

After the clash, four vehicles with Hamas police drove in to break up the crowd, using sticks to push people away from the border. Later in the day, the border reopened to allow those stranded on the wrong side to get back home.

The border breach had briefly boosted the popularity of Hamas, which seized control of Gaza by force in June. After seven months of tight border closures, imposed by Israel and Egypt in response to the Hamas takeover, many Gazans had rushed into Egypt to stock up on basic supplies, including cement, fuel, medicines and spare parts for cars.

But the euphoria vanished when the border was resealed.

Prospects for a border deal dimmed further Monday amid an investigation into whether two young men from Gaza used the border breach to sneak into Egypt and from there to Israel, where they blew themselves up in a shopping center in the southern town of Dimona.

The attack, which killed an Israeli woman and wounded nine people, followed warnings Sunday by the head of Israel's Shin Bet security agency that militants were using the breach to slip out of Gaza and carry out attacks. The bombing further embarrassed Egypt and heightened pressure to keep the border closed.