Israel launched its military offensive against Gaza on 14 November, marking the latest eruption in a conflict with Palestinian militants which has raged between the two sides for years. The latest violence has left dozens of people dead, many of them civilians, and shows no sign of ending soon.
Here is a guide to what has happened so far and how the situation may evolve.
How did this start?
Israel's offensive on Gaza began with an air strike that killed the commander of Hamas's military wing, Ahmed Jabari, whom it accused of responsibility for "all terrorist activities against Israel from Gaza" over the past decade.
The Israel Defense Forces (IDF) subsequently announced the start of Operation Pillar of Defence, which it said was intended to protect Israeli civilians from rockets and mortars fired by militants in Gaza, as well as cripple Hamas's capability to launch attacks.
Israeli Prime Minister Benjamin Netanyahu said the operation was launched because he could no longer "accept a situation in which Israeli citizens are threatened by the terror of rockets".
Israeli air strikes on what it said were rocket-storage sites and on Hamas facilities, and a surge in Palestinian rocket-fire into Israel, ensued.
Hamas, which has governed Gaza since 2007, said Jabari's assassination had "opened the gates of hell".
Although Jabari's killing signalled the start of Israel's offensive, it was preceded by spates of deadly cross-border violence which saw Palestinian militant groups, including Hamas's Qassam Brigades, firing hundreds of rockets into southern Israel and the Israeli military shelling Gaza and carrying out air strikes.
What do both sides want?
The Israeli government has said Operation Pillar of Defence has two main goals - to protect Israeli civilians and "cripple the terrorist infrastructure in Gaza". Mr Netanyahu has insisted that he is not seeking to topple Hamas.
On 18 November, the prime minister announced that the IDF had attacked more than 1,000 "terrorist targets" and had achieved "significant hits on weapons aimed at Israeli citizens, as well as on those who use the weapons and those who dispatch them". Israel has said it is doing its utmost to avoid civilian casualties, although more than half of those killed in Gaza have been women and children, according to Hamas officials.
Israeli military sources say most of the Iranian-made Fajr-5 and M75 medium-range missiles which had been in the possession of Hamas and the Islamic Jihad militant group were destroyed during the first few hours of the offensive. However, some have landed near Tel Aviv and Jerusalem, and Israel has struggled to contain shorter-range rockets.
At the start of the offensive, Hamas's Deputy Foreign Minister Ghazi Hamad insisted it was not the aggressor and did not want to see the violence escalate. "We still say that we are the victims of the Occupation and we are the target," he said. But Mr Hamad also argued that Hamas had a right to defend its people and would respond to Israeli attacks, warning: "If Gaza is not safe, your towns will not be safe also."
Could there be an Israeli ground offensive?
Mr Netanyahu told a cabinet meeting on 18 November that Israel was "prepared for a significant expansion of the operation". He made no mention of the possibility of a ground offensive, but has said one cannot be ruled out. Israeli Defence Minister Ehud Barak earlier said the Israeli military would "do everything that is necessary to achieve peace and quiet".
The Israeli government has approved the calling up of 75,000 army reservists in apparent preparation for a ground offensive. Some 31,000 have already been summoned. Several infantry and armoured brigades have already been deployed in the Negev desert, near Gaza. Veteran Israeli commanders say about 30,000 troops reportedly took part in the 2006 Lebanon war and 20,000 in Operation Cast Lead - Israel's offensive against Gaza in 2008-09.
Analysts say Israeli commanders believe the build-up will help deter Hamas, making it clear Israel's intentions are serious, but also making it possible to launch an offensive were Hamas to refuse a ceasefire.
Since the end of Operation Cast Lead, Hamas's military wing has been preparing for another ground offensive. It is believed to have about 10,000 active fighters and 20,000 in reserve. The group has also built bunkers, improved its military technology and acquired more sophisticated and powerful weapons. Although the Qassam Brigades lost its leader, its command and control capability is still functioning.
How has the international community responded?
US President Barack Obama said on 18 November that it was "preferable" that Israel did not launch a ground offensive on Gaza, but reiterated that he was "fully supportive of Israel's right to defend itself from missiles" despite mounting Palestinian civilian casualties. Mr Obama said rockets fired into Israel by Hamas had been the "precipitating event" in the conflict and had to be stopped. The US, he added, had been "actively working with all the parties in the region" to bring about a de-escalation of violence.
UK Foreign Secretary William Hague said Hamas bore "principal responsibility" for the current conflict but warned that a ground invasion would "lose Israel a lot of the international support and sympathy they have in this situation".
On 16 November, EU foreign affairs chief Catherine Ashton said she was deeply concerned at the violence and deplored the loss of civilian lives. She said the rocket attacks were "totally unacceptable and must stop", but also said Israel had to ensure that its response was "proportionate".
However, there has been strong condemnation of Israel's actions from long-time Western allies in the region, notably Egypt, Turkey, Tunisia and Qatar. Egypt's President, Mohammed Mursi, said he would "not leave Gaza on its own", condemning what he called Israel's "blatant aggression against humanity". His Prime Minister, Hisham Qandil, travelled to Gaza on 16 November, where he pledged to work for a truce "to stop the aggression".
On 18 November, Arab foreign ministers gave their backing to the Egyptian peace effort and agreed to send a delegation to Gaza headed by the Arab League's Secretary General, Nabil al-Arabi. The ministers condemned what they described as Israeli "aggression" and expressed "complete discontent" with the UN Security Council's lack of action.
What are the prospects for a ceasefire?
An Israeli delegation travelled to Cairo on 18 November to discuss with Egyptian officials the possibility of a ceasefire. Israel's Foreign Minister, Avigdor Lieberman, has said that "the first and absolute condition of any truce" is the end of Palestinian rocket-fire from Gaza. "We want a long-term arrangement," Mr Lieberman added. Past ceasefires between Israel and Hamas have been short-lived.
On 17 November, the Egyptians held talks with a Hamas delegation. A senior Hamas official said it wanted guarantees that "all acts of aggression and assassinations would stop". Another official said the group would seek assurances from the United States that it would be the "guaranteeing party". Hamas is also said to want an end to Israel's blockade of Gaza as part of any deal.
What does this mean for the Middle East peace process?
Hamas has not been part of any peace talks with Israel, and two decades of on-off negotiations between Israel and the Palestinian Authority (PA) in the West Bank has failed to produce a permanent settlement. The latest round of direct negotiations broke down in 2010.
Even before the Israeli offensive on Gaza began, the two sides had rarely appeared further apart and the conflict more intractable. In January, several months of indirect "proximity talks" ended without any progress.
The Israeli and US governments have also been angered by PA President Mahmoud Abbas's plan to submit on 29 November a request to the UN General Assembly for Palestine to become a "non-member observer state". The Palestinians argue that this would strengthen their hand in peace talks. Israel and the US say the only way to achieve an independent state is through direct negotiations.
On 18 November, Mr Obama said if the situation in Gaza worsened, "the likelihood of us getting back on any kind of peace track that leads to a two-state solution is going to be pushed off way into the future".
<an over view from BBC>