Cairo - Four people were killed and three went missing in the collapse of an underground tunnel Sunday north of the Rafah border crossing between Gaza and Egypt, security sources said.

Sources from the militant group Hamas informed Egyptian authorities of the incident.

Egypt is still searching for the missing people inside the tunnel, the source said.

The identities of the dead and missing were not immediately known, the source said.

Gaza City - A Palestinian policeman was killed early Friday in an explosion in the police headquarters in Gaza City, according to an official in the de-facto Hamas government.

Ministry of Interior spokesman Ihab Ghussein said the powerful explosion killed Ala Ijleh, 20, from Gaza City.

He said Ijleh, who belongs to the bomb squad in the police force, was killed while attempting to detonate an explosive device discovered in the bomb squad section of the Arafat Police City.

No one else was hurt in the explosion, which sparked a fire in the building, the spokesman said.

Meanwhile, Palestinian fighters engaged an Israeli force which crossed the southern Gaza border with Israel near the town of Khuza'a, east of Khan Younis.

Gaza - Extending an olive branch to Palestinian President Mahmoud Abbas ahead of unity talks in Cairo next month, the Islamic Hamas movement released 17 members of the president's Fatah movement it had detained in the Gaza Strip in July.

The 17 were among dozens of Fatah activists arrested by Hamas police after a car bomb killed five Hamas members in Western Gaza City in late July.

Gaza - A ship loaded with international pro-Palestinian activists intent on breaking Israel's blockade of the coastal salient docked in Gaza Wednesday morning, despite a vow by Israeli officials not to let the vessel enter the enclave's territorial waters.

"The Dignity," with 27 people on board, including Western human- rights activists, peace activists, journalists, and European and Palestinian lawmakers, moored at 8 am
(0600 GMT), officials in naval police force of Hamas, which controls the territory, said.

Gaza - A ship loaded with international pro-Palestinian activists intent on breaking Israel's blockade of the coastal salient docked in Gaza Wednesday morning, despite a vow by Israeli officials not to let the vessel enter the enclave's territorial waters.

"The Dignity", with 27 people on board, including Western human- rights activists, peace activists, journalists, and European and Palestinian lawmakers, moored at 8 am 
(0600 GMT), officials in naval police force of Hamas, who control the territory, said.

The boat left Cyprus on Tuesday and the activists plan to remain in the Strip for four days, Jamal al-Khodary, the head of Gaza-based Popular Committee Against the Siege, said.

Gaza - Three Palestinians were killed Saturday when a tunnel used for smuggling beneath the Gaza-Egypt border collapsed, medics and witnesses said.

Witnesses said the three had been working on the tunnel, which collapsed near its end on the Egyptian side. The dead were taken to Egyptian hospitals in the northern Sinai city of al-Arish.

Palestinian medics said the deaths brought the number of Palestinians killed in such tunnels to 50.