The most violent conflagration in more than a year between Israel and Gaza militants extended into a second day on Saturday, with exchanges of rocket fire and airstrikes that destroyed residential buildings, and pushed the death toll to at least 24, according to Palestinian health officials.
Palestinian health officials said that among those killed in the strikes were six children, but Israel said some civilian deaths were the result of militants stashing weapons in residential areas, and that in at least one case, a misfired Palestinian rocket killed civilians, including children, in northern Gaza.
The current round of fighting, which began on Friday with Israeli airstrikes, has mainly pitted Israel against Islamic Jihad, the second-largest militant group in Gaza. Hamas, the dominant militia in Gaza, has so far stayed away from direct involvement, raising hopes that the conflict will not escalate into a larger war.
The renewed tensions highlighted the challenge of preventing flare-ups in Israel and the occupied territories when both the Israeli and Palestinian leaderships are divided and politically weak, international attention is elsewhere and there is little hope of ending the 15-year blockade of the Gaza Strip by Israel and Egypt.
“There is no end in sight for this cycle, and no actor seems to wish to construct any more stable alternative,” said Prof. Nathan J. Brown, an expert on the Middle East at George Washington University.
The Israeli military said on Saturday that it had struck residences belonging to operatives of Islamic Jihad, which it described as weapons stores. Military officials said that prior warnings were given, and that the buildings were evacuated before the strikes.
The head of the operations directorate of the Israeli military, Maj. Gen. Oded Basiuk, said that the two-day operation meant that “basically, the entire security leadership of the military wing of Palestinian Islamic Jihad in Gaza has been eliminated.”
Islamic Jihad confirmed the death on Friday of its military leader in northern Gaza, Taysir al-Jabari, but did not confirm Israeli claims that an airstrike on Saturday had killed its commander in southern Gaza, Khaled Mansour.
Following Friday’s airstrike that killed Mr. al-Jabari, Islamic Jihad launched rocket and mortar barrages that sent thousands of Israelis into bomb shelters overnight.
On Saturday, Islamic Jihad and other smaller militant groups in Gaza fired rockets at Israeli towns near the territory and cities farther afield in central Israel, including Tel Aviv, sending Israeli beachgoers rushing for cover. Israel said Islamic Jihad had fired 400 rockets over the two days.
Israel said it ordered the airstrikes to prevent an imminent attack from Islamic Jihad in Gaza. Earlier in the week, Israel had arrested a senior figure from the group in the West Bank, leading to threats of reprisals. Israel said its airstrikes aimed to stop Islamic Jihad from following through on those threats.
On Saturday night, Israel signaled that it was prepared to accept a cease-fire. Colonel Hecht, the Israeli military spokesman, said Israel would stop firing if Islamic Jihad stopped first.
At least two Israeli soldiers and a civilian were wounded, according to Israeli officials and news reports. But the majority of Palestinian rockets either fell on open areas or were intercepted by Israel’s Iron Dome air defense system, according to the military.
The only power plant in Gaza halted operations because of a freeze on fuel deliveries from Israel, further reducing power across large parts of the territory. A senior Israeli military official, speaking to reporters on Saturday on the condition of anonymity to comply with army rules, said Israel was liaising with Egypt about how to deliver more fuel to Gaza while under rocket fire.
Since an 11-day war in May last year, Israel has persuaded militias in Gaza to avoid violence by offering 14,000 work permits to Palestinian laborers in the territory — the highest number since Hamas seized control of the territory in 2007.
Roughly two million people live in Gaza and most receive no direct benefit from the new permits. But the permits nevertheless provide a crucial financial lifeline to thousands of families in the enclave, where nearly one in two residents are unemployed and only one in 10 have direct access to clean water, according to UNICEF.
Wary of losing that concession, particularly while it is still rebuilding military infrastructure damaged during the last war, Hamas has avoided a major escalation all year in Gaza while still encouraging unrest and violence in Israel and the West Bank.
But Islamic Jihad, which, unlike Hamas, does not govern Gaza, is less motivated by small economic concessions.
This is at least the sixth surge of violence in Gaza since Hamas seized control in 2007, prompting Israel and Egypt to begin their blockade. Israel is not prepared to end the blockade while Hamas is in power, and while Hamas does not recognize Israel and refuses to end its armed activities.
In the absence of a formal peace process to end the conflict, the repeated rounds of violence in Gaza, as well as intermittent bursts of back channel diplomacy, are considered alternative ways to renegotiate the terms of the Gaza blockade.
“Absent anything more lasting, both sides resort to violence not to defeat the other side — much less eliminate it — but just to adjust the terms, and also to play to home audiences,” said Mr. Brown, the Middle East expert.
The last two days of conflict in Gaza can be linked back to a spike in violence across Israel and the West Bank several months ago. A spate of Palestinian attacks on civilians in Israel in April and May led to an increase in Israeli raids on the West Bank, particularly in areas where Israeli officials said the attackers and their abettors came from.
The Israeli campaign resulted in almost nightly arrests across the West Bank over the past several months, and culminated in the arrest this week of Bassem Saadi, a senior Islamic Jihad figure.
The new round of violence also served as a reminder of Iran’s role in the Israeli-Palestinian conflict. While Tehran’s nuclear program is seen by Israel as the biggest threat, Iran also exerts regional influence by providing financial and logistical help to militant proxies across the Middle East, like Hezbollah, in Lebanon, and Islamic Jihad and Hamas in Gaza.
The crisis was also the first major test for Yair Lapid, Israel’s caretaker prime minister who took office last month after his predecessor’s government collapsed.
The military operation is a risky gambit for Mr. Lapid, a centrist often derided for lacking security experience by his main rival, Benjamin Netanyahu, Israel’s longest serving prime minister who now leads the opposition.
Although it gives Mr. Lapid the chance to prove his security credentials to the Israeli electorate, it also leaves him open to accusations that he is endangering both Israeli and Palestinian lives.
In Gaza, mourners were already counting the costs from the two days of fighting.
Among the individuals killed since Friday was a 5-year-old girl, Alaa Qadoum. Her relatives wrapped her body in a white shroud and Palestinian flags for burial on Friday. A bright pink bow tied most of her hair back.
“Alaa was a fun little girl who did not hurt anyone,” her grandfather, Riad Qadoum, 56, said in an interview. “She was not firing rockets or fighting anyone.”
Colonel Hecht, the Israeli military spokesman, said the child’s father was a senior Islamic Jihad commander, but would not say whether he was targeted in the airstrike that killed his daughter.
The father was wounded in the same airstrike and is in critical condition, according to doctors at the hospital, where he was being treated. Alaa’s brother was also wounded, the grandfather said. The family would not comment on whether the father was linked to Islamic Jihad.
The senior Israeli military official who briefed reporters on Saturday said he was aware of the reports of her death, adding that any civilian deaths would be investigated. But Israel has in the past blamed militants for civilian deaths, saying they often station their rocket launchers and bases close to civilian homes and infrastructure.
In a separate briefing for reporters at a military base near the Gaza border in late July, senior Israeli military officials, speaking on the condition of anonymity under army rules, presented maps showing the routes of what they said were parts of a militant tunnel network, including sections running beneath roads around a major university in Gaza.
The length and scope of the fighting will partly depend on Hamas’s involvement.
Ismail Haniyeh, the leader of the political bureau of Hamas, said on Friday that the group was “open to all directions.”
But tensions could be compounded in Jerusalem on Sunday, when Jews will mark Tisha B’Av, the commemoration of the destruction of two ancient Jewish temples, on a site now sacred to both Jews and Muslims. Large numbers of Jewish worshipers are expected to visit that site, known as the Aqsa Mosque compound or the Temple Mount.
Such visits often prompt unrest that can lead to more rocket fire from Gaza.
Raja Abdulrahim, Carol Sutherland and Fady Hanona contributed reporting.