Israeli troops shot and killed a teenage Palestinian militant along the country's border with Gaza Thursday in the first deadly incident since the two sides reached a cease-fire last month.

A faction of the militant group Al Aqsa Martyrs' Brigades said the 18-year-old killed in Gaza belonged to its ranks. It vowed revenge and claimed responsibility for two rockets fired at southern Israel after the shooting.

"We will not let this crime pass silently," the group said in a text message to reporters.

Al Aqsa Martyrs' Brigades, which had previously violated the June 19 truce by firing rockets at Israel, did not say what the militant was doing along the border.

Hamas, the Islamic militant group which rules Gaza, said it considered the pre-dawn shooting a violation of the cease-fire, but did not vow revenge. Al Aqsa said Hamas police arrested two militants who fired the two rockets Thursday.

"The Palestinian factions show a great commitment to making this understanding successful, but the occupation must also be committed to their obligations," Hamas spokesman Sami Abu Zuhri said.

Israeli troops fired on the youth after he did not respond to warning shots and calls to stop, a military spokesman said. The soldiers thought he was armed but, after inspecting the body, found that he was not, the spokesman said.

The truce that took hold in Gaza last month was meant in its initial phase to halt rocket and mortar fire on southern Israel and to ease harsh Israeli economic sanctions imposed after Hamas overran the territory a year ago. But sporadic militant attacks have continued, provoking Israel to close its crossings into the coastal strip of 1.4 million Palestinians and keep its blockade more or less intact.

The truce does not extend to the West Bank, which is ruled by moderate Palestinian President Mahmoud Abbas, Israel's partner in peacemaking.

In the West Bank, Israel pressed forward with a crackdown on facilities it says are linked to Hamas. In the fourth day of operations in the city of Nablus, Israel closed a clinic and TV station, and raided a mosque, a newspaper and other offices.

In recent months, the Israeli military has been clamping down on Hamas operations in the West Bank in an effort to prevent the violently anti-Israel group from overrunning that territory as it did Gaza.

Dozens of military jeeps and trucks entered Nablus before dawn Thursday, witnesses said. Troops raided a medical clinic, confiscating computers and documents, and a local TV station, newspaper, mosque and women's organization. Some of the offices were ordered closed, and troops also confiscated five school buses, they said.

The Israeli military confirmed an operation against Hamas in Nablus, but offered no details.

Palestinian Interior Minister Abdel Razek Yehiyeh said the Israeli raids were undermining the Palestinian government's efforts to establish law and order in the West Bank.

"We condemn these practices and see them as sabotaging our security achievements," he told a news conference in Ramallah.

This week Israel ordered a Nablus mall closed down, charging it is owned by Hamas. The registered owners denied that.

Palestinian Prime Minister Salam Fayyad visited the mall Thursday and called on shopowners to defy the order to close. He said Israel has no authority over the mall.

Also Thursday, Israeli troops raided the southern West Bank city of Hebron, arresting eight Palestinians affiliated with Hamas and demolishing a house, witnesses said. The military did not immediately comment.

Israeli construction plans for east Jerusalem were also raising tensions with Palestinians. Palestinian negotiator Yasser Abed Rabbo said Palestinians might freeze their peace talks with Israel over those plans.

The Palestinians hope to establish the eastern sector of the city as capital of their future state, and see continued Israeli construction there as undermining that goal.

Since renewing negotiations with the Palestinians in November, Israel has disclosed plans to build more than 3,000 apartments in east Jerusalem and the adjoining West Bank. Israel captured both areas in the 1967 Mideast war.