Palestinian hospital sources and witnesses said two Palestinian youths were shot dead and seven people werw injured Thursday by IDF troops in the town of Rafah, on Gaza's border with Egypt.

The sources said the troops opened fire as children threw rocks and bottles at IDF tanks tearing down structures.

One of the seven was in critical condition, they said.

The IDF said that soldiers found a tunnel used for smuggling arms across the border. The tunnel was in a house, the military statement said, and soldiers blew it up.

During the operation, Palestinians fired rifles and threw hand grenades, firebombs and rocks at the soldiers, who returned fire, the military said.

Witnesses: Troops blasting Nablus government building IDF soldiers set off explosives inside the main Palestinian government building in the West Bank city of Nablus on Thursday, witnesses said.

The IDF had no immediate comment.

Wafa Khdeir, 42, a resident, said she saw IDF soldiers fire tank shells at the large building and ordered everyone out. No one emerged, and then the soldiers set off explosives at the door and entered.

Several hours later, after searching the three-story fortress-like building, they blew up a room in the compound, she said. No casualties were reported.

Nablus governor Mohammed Aloul has his office in the building, but he was not there because of the curfew. Security forces had headquarters in the building but moved out in April after a previous IDF offensive.

Nablus was the only West Bank center under curfew through the day Thursday, according to the military. As a result, few people were inside the building.

Al-Aqsa Martyrs' Brigades snatches two for aiding Israeli A brother and sister from the West Bank town of Tul Karm were kidnapped Thursday by the Al-Aqsa Martyrs Brigades, the military wing of the Fatah, on the suspicion of aiding Israel.

The kidnappers are threatening to execute the two, who are the niece and nephew of Ikhlas Khouli, the 35-year-old mother of seven who was seized from her Tul Karm home and shot dead Saturday after admitting to collaborating with Israel.

Khouli's sister and the mother of the two arrested Thursday was also interrogated, but was released after admitting her collaboration with Israel. She said that admitted to the charges after being tortured.

Palestinian sources said PA officials were pressuring the Al Aqsa Martyrs' Brigades not to execute the siblings.

PA cancels Ben-Eliezer meet after 4 Palestinians killed Palestinian Authority Interior Minister Abdel Razak Yehiyeh and Mohammed Dahlan, advisor to Yasser Arafat, have canceled their meeting Thursday with Defense Minister Benjamin Ben-Eliezer, citing the deaths of four Palestinian civilians by IDF tank fire in the Gaza Strip the previous day, Israel Radio reported.

The three were to discuss progress in the "Gaza and Bethlehem First" plan. A meeting scheduled for Wednesday was canceled by Ben-Eliezer due to shooting in the Gaza Strip.

Ben-Eliezer expressed regret Thursday over the incident, and in a statement referred to the victims as "innocent" civilians.

The four, including a mother and her two sons, were killed Wednesday when IDF tank shells landed in a Bedouin encampment in the Gaza Strip, residents and doctors said, as IDF troops searched the seacoast for the second night in a row.

The dead were identified as Rawaida Hajien, 50, two of her sons, Ashraf, 23, and Mehad, 17, and a cousin, Mohammed, 20. Hajien's 4-year-old son, Said, was critically wounded, and three other people were hurt, doctors said.

According to an army spokesperson, a preliminary investigation on the incident has found that an IDF force near the northern Gaza Strip settlement of Netzarim detected a number of individuals crawling near a zone in which Palestinians are prohibited. The troops opened fire at the suspected individuals and hit them.

The army pointed out that several attempts have been made to carry out attacks targeting civilians and IDF troops in the vicinity of Netzarim. The IDF statement said that it regrets hurting innocent civilians and will continue to investigate the circumstances of the incident.

Hamas vows to avenge deaths of Palestinian civilians The militant Hamas organization Thursday vowed to mount further attacks on Israeli civilians to avenge the deaths of the four.

"Members of one family were killed in cold blood," senior Hamas leader Mahmoud al-Zahar told Reuters as he stood beside the bodies of the dead in the morgue of Gaza's main hospital. "When there are killings of Palestinian civilians, Israel can expect killings of its civilians."

During Wednesday's military operations, IDF tanks moved into Palestinian territory near the settlement of Netzarim, cutting a main road, residents said, as five IDF gunboats patrolled the shore, where a day earlier, Israeli forces fired at objects in the water, suspected to be packets of smuggled arms, which turned out to be refrigerators.

Residents said the tanks fired machine guns and shells. Red Crescent rescue workers said six shells fell in a Bedouin encampment west of the settlement, hitting two houses.

The IDF said it was checking the incident.

Yehiyeh says to discuss IDF exit from Hebron with Ben-Eliezer In an interview published Thursday in the Beirut daily A-Nahar,, Yehiyeh said that he intended to raise the subject of an IDF withdrawal from the West Bank city of Hebron when he meets with Ben-Eliezer.

"We do not owe (Israel) anything in exchange for the withdrawal," Yehiyeh said in the interview. "We are trying to fulfill our commitment to our people to establish law and order and to prevent anyone from taking the law into his own hands."

According to Yehiyeh, in recent days the PA security apparatus has made an attempt to reestablish its presence in the Gaza Strip and to deploy security personnel to several posts, including those destroyed by Israel. The goal, he said, is to return the situation in these areas to that which existed "before they were destroyed."

According to the Palestinian security chief, the process "will take some time." He also said that the return of Palestinian security personnel to the posts was being done in accordance to agreeements reached a few days ago between the Palestinians and Ben-Eliezer. Yehiyeh also said that Israel must now withdraw its forces from the Gaza Strip, as was agreed upon by the sides.

Defense sources said earlier in the week that Ben-Eliezer is expected to tell Yehiyeh that it is premature to apply the same procedure to Hebron, but he is also expected to say Israel has been encouraged by the quiet in Bethlehem and has noted a sharp decline in violent incidents in Gaza.

Defense Ministry sources said Ben-Eliezer will tell Yehiyeh to disregard reports in the Israeli press about Israel backing down from the plan and that its progress is dependent on the efforts made by the PA to prevent terror.

The sources said there has been a marked decline in incidents in the Gaza Strip, but it's still not enough. "They could do a lot more, without getting into an internal conflict," said the source. "We'll encourage them to deploy forces in sensitive areas."