The confessions came as violence continued on Israel's volatile front with the Gaza Strip. Palestinian militants bombarded Israel with some 40 rockets and mortars, drawing Israeli airstrikes in retaliation, and at least eight Palestinian militants were killed. As Israel pressed ahead with a mobilization of forces along the Gaza border, the Hamas militant group vowed revenge, saying "the enemy will pay a tremendous price."
Army spokesman Lt. Col. Peter Lerner said Israel was "prepared for a potential deterioration" in Gaza "with potential to use military force as required."
The region has been on edge for weeks since three Israeli teenagers were kidnapped and killed in the West Bank. Last week, hours after the Israeli teens were buried, 16-year-old Mohammed Abu Khdeir was abducted from outside his home in east Jerusalem, and his charred remains were found shortly afterward in a Jerusalem forest. His death triggered days of violent protests in Arab areas of Jerusalem and northern Israel.
The Jewish suspects, all from the Jerusalem area, have not been identified, and remained in custody Monday. The official spoke on condition of anonymity because of the continuing investigation.
Israel's Shin Bet internal security agency has put a gag order on the case, allowing few details, such as the suspects' identities or backgrounds, to be published, and even blocking lawyers' access to the suspects.
"I don't even know what they look like because the (Shin Bet security service) even has an order against me receiving a picture," said Naftali Werzberger, a lawyer for one of the suspects, adding that his client was prohibited from receiving details that he is represented by a lawyer at all.
"The families are in shock," he added. "No one among the suspects has a violent past or tendency and they can't explain how we got to this point where their children were arrested as suspects for acts that are very, very serious."
Palestinians say that Abu Khdeir's death was a revenge killing in response to the abductions and killings of the three Israeli teens.
Prime Minister Benjamin Netanyahu has condemned Abu Khdeir's death and tried to calm the public. On Monday, he called Abu Khdeir's father, Hussein, to express his condolences.
"I would like to express my outrage and that of the citizens of Israel over the reprehensible murder of your son," a statement quoted Netanyahu as saying.
"We acted immediately to apprehend the murderers. We will bring them to trial and they will be dealt with to the fullest extent of the law. We denounce all brutal behavior, the murder of your son is abhorrent and cannot be countenanced by any human being," he said.
Hussein Abu Khdeir, father of the slain boy, said he was not certain he spoke to Netanyahu.
"Maybe he called, I don't know," he said. "Tons of people called me this morning to apologize for what happened to my son. Some of them were crying. But I don't know if Netanyahu was one of them," he said.
The discovery Sunday that a group of Jewish men, including some minors, were suspected in the grisly death of Abu Khdeir, who was still alive when he was set on fire, set off nationwide anguish in Israel and raised questions about whether the charged atmosphere in the country had contributed to the killing.
"Shame. That is the word," wrote Sima Kadmon, a commentator in the mass daily Yediot Ahronot. "For the murder of Mohammed, there is shame. Immense shame and disgrace over the fact that such a thing happened among us, we who are so certain that it could not happen among us, that only Arabs can be so cruel."
Israeli President Shimon Peres, a Nobel peace laureate, and the man who is to succeed him later this month, Reuven Rivlin, co-authored a front-page article in the same newspaper.
"In the state of Israel, there is no difference between blood and blood," the two men wrote. "The choice is in our hands: To give in to the destructive worldview posed to us by the racists and the extremists, or to fight it unconditionally; to give in to wild and vicious Muslim or Jewish terrorists — or to put an end to it by all means possible."
Also Monday, Israeli police said a border policeman had been temporarily suspended from special operations and transferred to a different position until the completion of an investigation into the apparent police beating of Tariq Abu Khdeir, a Palestinian-American teenage cousin of the murdered Palestinian teen.
Despite his home detention, Tariq Abu Khdeir traveled to the West Bank town of Ramallah to meet President Mahmoud Abbas.
"Justice has not been served. They still have a lot of stuff to do. They still have to go through a lot of things. We have to let them who is right and what's wrong," Tariq Abu Khdeir said.
In recent weeks, Palestinian militants in Gaza have fired more than 200 rockets and mortars toward Israel, drawing dozens of Israeli airstrikes in retaliation. Some 40 rockets were launched Monday, including one that reached Beersheba, a major city about 50 kilometers (30 miles) away from Gaza, and Israel said it carried out airstrikes on at least 14 militant sites including "concealed rocket launchers" in Gaza overnight.
Hamas, the militant group that controls Gaza, claimed six of its men were killed in Israeli airstrikes overnight, while two other militants were killed separately. But the Israeli military said the Hamas fighters died in an accidental blast set off in an explosives-packed tunnel they may have been using to try to sneak into Israel. The military said it had targeted the tunnel late last week.
Meanwhile, Israel's foreign minister, Avigdor Lieberman, dissolved a political alliance with Netanyahu, in large part because of their differences over Gaza.
Netanyahu has advocated a measured response to the rocket fire, while Lieberman has called for much tougher action. Israeli Cabinet ministers were meeting Monday to discuss the situation.
Associated Press journalist Yousur Alhlou contributed to this report.
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