An Israeli soldier was killed by a bomb on the border with the Gaza Strip on Tuesday and troops then killed a Palestinian, violence that strained a ceasefire and left people in Gaza fearing further Israeli attacks.
Ten days after Israel halted a devastating, three-week air and ground offensive that killed 1,300 people in the enclave, a group using an uncommon name not previously linked with the ruling Hamas Islamist movement claimed the attack on a patrol.
But, on the day U.S. President Barack Obama's new envoy arrived in the Middle East with the message that the "moment is ripe" for peace talks, Israeli leaders facing an election in two weeks promised voters they would hit back hard at Hamas itself.
Hillary Clinton, Obama's new secretary of state, said Israel had a right to defend itself against rockets that Hamas has fired from Gaza over recent years.
"I don't care who fired," said Israeli Foreign Minister Tzipi Livni, who is leading the ruling party in the campaign for the Feb. 10 ballot. "Hamas controls Gaza and is responsible for everything that happens. Whenever they fire at me from Gaza, set off a bomb or launch a missile or smuggle (weapons), Israel will respond."
Hours later, a senior militant from the Hamas-allied Popular Resistance Committees (PRC) was wounded, along with a bystander, in an Israeli air strike, militants and medics said.
A group using the Islamist name Tawhid-wa-Jihad (Monotheism and Struggle) distributed a two-minute video showing an army jeep engulfed by an explosion as it drove along a road. As other soldiers arrived at the rural scene on foot they came under rifle fire and were then obscured by a second heavy blast.
Residents near Deir al-Balah, in the central Gaza Strip close to where the soldier was killed, said that toward evening tanks and armoured bulldozers were manoeuvring around orchards and wells, causing damage in a familiar punitive tactic.
Hamas spokesman Sami Abu Zuhri did not claim responsibility but praised the bomb attack on the troops as "a natural response to the crimes of the occupier". Two Palestinians were killed last week in incidents blamed on Israeli fire.
The early morning skirmishing was the bloodiest since the 22-day Israeli offensive ended in ceasefire declarations.
The Israeli military said a bomb was detonated against its forces on the Israeli side of the border fence near the Kissufim crossing, killing one soldier and wounding three.
Israeli fire into the Gaza Strip shortly afterwards killed a Palestinian who medics said was a 27-year-old farmer.
Palestinians living near Kissufim crossing told Reuters they saw at least two gunmen move towards the border fence in the morning mist. They later heard explosions and gunfire.
Israel said that in response to the attack it shut down the crossing points through which flow the humanitarian aid and other supplies on which the 1.5 million people of Gaza depend. Aid agencies have been urging Israel to ease restrictions on trade to help rebuild thousands of homes destroyed in bombing.
Militants have previously directly attacked the transit crossings and demanded an end to Israel's blockade on Gaza.
Ten Israeli soldiers were killed during the offensive that began a month ago on Dec. 27. Three Israeli civilians also died.
Hamas and Israel declared separate ceasefires and are negotiating through Egyptian mediators on a longer-term truce. Hamas wants Israel to end its blockade. Israel wants guarantees Hamas cannot renew rocket fire on its towns.
In an interview broadcast on Al Arabiya, Obama said Israel and the Palestinians should resume peace negotiations.
His envoy George Mitchell arrived in Egypt on Tuesday and is due in Jerusalem on Wednesday for talks with Israeli leaders.
But Palestinian President Mahmoud Abbas said in a speech in the West Bank city of Ramallah he would toughen his stance in peace talks following Israel's Gaza offensive. He said he would tell Mitchell it proved Israel was not intent on peacemaking.
"Israel does not want peace, otherwise it would not have done this. We need to understand this and tell it to those coming from Europe and America. Israel wants to waste time to strengthen facts on the ground with settlements and the wall."
Egypt said on Tuesday that it proposed a meeting on Feb. 22 to try to end a schism between Hamas, which won a parliamentary election in 2006, and Western-backed Abbas, whose power has been restricted to the Israeli-occupied West Bank since Hamas seized control of Gaza 20 months ago.
(Additional reporting by Lin Noueihed in Dubai, Adam Entous in Gaza and Allyn Fisher-Ilan and Jeffrey Heller in Jerusalem, Andrew Hammond in Ramallah)