The Israeli military has intensified its assault on Gaza, as Palestinian militants continue to fire rockets into Israel on the fifth day of hostilities.
Israel’s army said air and ground forces were involved in attacks on Friday but had not entered Gaza.
A BBC reporter in Gaza said there was heavy shelling involving gunboats, fighter jets, and helicopters.
More than 100 people have been killed in Gaza and seven have died in Israel since fighting began on Monday.
Meanwhile, Jewish and Israeli-Arab mobs have been fighting within Israel, prompting its president to warn of civil war.
Defence Minister Benny Gantz ordered a “massive reinforcement” of security forces to suppress the internal unrest that has seen more than 400 people arrested.
In a statement released early on Friday morning, Israeli Prime Minister Benjamin Netanyahu said the Israeli military operation against Palestinian militants in Gaza would continue for as long as necessary. He said Hamas, the Islamist group that rules Gaza, would pay a heavy price.
A Hamas military spokesman said the group was ready to teach Israel’s military “harsh lessons” should it decide to go ahead with a ground incursion.
This week’s violence in Gaza and Israel is the worst since 2014. It was initially fuelled by weeks of Israeli-Palestinian tension in East Jerusalem which led to clashes at a holy site revered by both Muslims and Jews. This spiralled into an incessant exchange of Palestinian rocket fire and Israeli airstrikes.
Shortly after Mr Netanyahu’s statement, video footage showed explosions lighting up the sky over Gaza City.
Rocket barrages from Gaza soon followed, with reports of attacks on the Israeli cities of Ashkelon, Ashdod, Beersheba and Yavne among other areas.
Hours earlier, Israel’s military called up 7,000 army reservists and deployed troops and tanks near its border with Gaza.
Israel’s military said a ground offensive into Gaza was one option being considered but a decision had yet to be made.
As fighting entered its fifth day, United Nations Secretary General António Guterres called for “an immediate de-escalation and cessation of hostilities in Gaza and Israel”.
His plea echoed that of other diplomats whose calls to Israeli and Palestinian leaders have so far failed to produce a ceasefire agreement.
In other developments on Thursday:
- Three rockets were fired from Lebanon into the sea off the coast of northern Israel, the Israel Defense Forces (IDF) said. No group claimed the attack but several militant groups operate in Lebanon, including Hezbollah, which fought a month-long war with Israel in 2006
- Israel’s military said it had hit targets in Gaza that included intelligence buildings, homes and businesses used by militants
- Hamas, meanwhile, fired further barrages of rockets towards Israel from Gaza. A spokesman for the group said it had shown “only a small part” of its capabilities
- Further violence broke out between Jewish and Israeli Arab groups in mixed towns and cities within Israel
- International airlines, including KLM, British Airways and Virgin Atlantic, have suspended services to Israel. Incoming flights were also diverted south from Tel Aviv’s main airport
At least 103 Palestinians have been killed since Monday, including 27 children, and more than 580 wounded, the health ministry in Gaza said. Officials in the territory said many civilians had died.
Israel says dozens of those killed in Gaza were militants, and that some of the deaths are from misfired rockets from Gaza.
In the Israeli city of Sderot, a young boy was killed when rocket fire from Gaza hit his home, and shrapnel penetrated the shelter he was hiding in.
Israel has also called up 10 reserve border patrol companies to help tackle the worst unrest between Arab and Jewish communities for many years. Political leaders have appealed for calm, and President Reuven Rivlin described the outbreaks of rioting in several towns and cities as “senseless civil war”.
There have been widespread calls for de-escalation, including from Israel’s ally the US, but little sign of the conflict easing.
A senior Hamas official said the group was ready for a “reciprocal” ceasefire if the international community pressures Israel to “suppress military actions” at the disputed al-Aqsa Mosque in Jerusalem.
However, Israeli military spokesman Hilda Zilberman said Israel was not seeking a ceasefire at the current time, the Times of Israel reported.
What caused the violence?
The fighting between Israel and Hamas was triggered by days of escalating clashes between Palestinians and Israeli police at a holy hilltop compound in East Jerusalem.
The site is revered by both Muslims, who call it the Haram al-Sharif (Noble Sanctuary), and Jews, for whom it is known as the Temple Mount. Hamas demanded Israel remove police from there and the nearby predominantly Arab district of Sheikh Jarrah, where Palestinian families face eviction by Jewish settlers. Hamas launched rockets when its ultimatum went unheeded.
Palestinian anger had already been stoked by weeks of rising tension in East Jerusalem, inflamed by a series of confrontations with police since the start of Ramadan in mid-April.
It was further fuelled by the threatened eviction of Palestinian families from their homes in East Jerusalem by Jewish settlers and Israel’s annual celebration of its capture of East Jerusalem in the 1967 Middle East war, known as Jerusalem Day.
The fate of the city, with its deep religious and national significance to both sides, lies at the heart of the decades-old Israel-Palestinian conflict. Israel in effect annexed East Jerusalem in 1980 and considers the entire city its capital, though this is not recognised by the vast majority of other countries.
Palestinians claim the eastern half of Jerusalem as the capital of a hoped-for state of their own.