JERUSALEM — Diplomatic efforts accelerated on Tuesday to end the lethal confrontation between Israel and Palestinian militants in Gaza on one of the most violent days yet in the conflict, as the United States sent Secretary of State Hillary Rodham Clinton to the Middle East and Egypt’s president and his senior aides expressed confidence that a cease-fire was close.
But by late evening there was no announcement, and Mrs. Clinton said she would be working in coming days to complete an agreement. Appearing beside Prime Minister Benjamin Netanyahu of Israel to speak briefly to the press, Mrs. Clinton said she hoped to achieve an end to the hostilities with a deal that moves “toward a comprehensive peace for all people in the region.” Mr. Netanyahu told Mrs. Clinton that if the rocket fire from Gaza stopped he was prepared to agree on a “long-term solution.”
The diplomatic moves to end the nearly week-old crisis came as the antagonists on both sides intensified their attacks before any cease-fire takes effect.
Israeli aerial and naval forces assaulted several Gaza targets in multiple strikes, including a suspected rocket-launching site near Al Shifa hospital, which killed more than a dozen people. Those deaths brought the total number of fatalities in Gaza so far to more than 130 — roughly half of them civilians, the Gaza Health Ministry said. A delegation visiting from the Arab League canceled a news conference at the hospital because of the Israeli aerial assaults as wailing ambulances brought victims in, some of them decapitated.
The Israeli assaults carried into early Wednesday, with multiple blasts punctuating the darkened Gaza skies.
Militants in Gaza fired a barrage of at least 200 rockets into Israel, killing an Israeli soldier — the first military casualty on the Israeli side since the hostilities broke out last week. The Israel Defense Forces said the soldier, identified as Yosef Fartuk, 18, died from a rocket strike that hit an area near Gaza. Israeli officials said a civilian military contractor working near the Gaza border was also killed, bringing the total number of fatalities in Israel from the past week of rocket mayhem to five.
Other Palestinian rockets hit the southern Israeli cities of Beersheba and Ashdod, and longer-range rockets were fired at Tel Aviv and Jerusalem, but neither main city was struck and no casualties were reported. One Gaza rocket hit a building in the Israeli city of Rishon Lezion, just south of Tel Aviv, injuring one person and wrecking the top three floors.
Senior Egyptian officials in Cairo said Israel and Hamas, the militant Islamist group that governs Gaza, were “very close” to a cease-fire agreement that could be announced within hours. “We have not received final approval but I hope to receive it any moment,” said Essam el-Haddad, President Mohamed Morsi’s top foreign affairs adviser.
Foreign diplomats who were briefed on the outlines of a tentative agreement said it had been structured in stages — first, an announcement of a cease-fire, followed by its implementation for 48 hours. That would allow time for Mrs. Clinton to involve herself in the process on the ground here and create a window for negotiators to agree on conditions for a longer-term cessation of hostilities.
By late evening, however, there was no word on an announcement, and Israeli television was saying the talks needed more time. In Cairo, Egyptian news reports quoted Hamas officials as blaming Israel for delaying a deal and an announcement was unlikely before Wednesday.
The announcement of Mrs. Clinton’s active role in efforts to defuse the crisis added a strong new dimension to the multinational push to avert a new Middle East war. Israel has amassed thousands of soldiers on the border with Gaza and has threatened to invade the crowded Palestinian enclave for the second time in four years to stop the persistent rockets that have been lobbed at Israel.
Mrs. Clinton, who accompanied President Obama on his three-country Asia trip, left Cambodia on her own plane immediately for the Israel, and upon arrival in the late evening went into immediate talks with Israeli leaders.
She was scheduled to visit the West Bank later to meet with Palestinian leaders and then go to Cairo to consult with Egyptian officials.
This article has been revised to reflect the following correction:
Correction: November 20, 2012
Because of an editing error, an earlier version of this article misspelled the family name of the Israeli soldier who was killed in a Palestinian rocket attack on Tuesday. He is Yosef Fartuk, not Yosef Faruk.