Two Palestinians were killed on Saturday as Israel unleashed a wave of air strikes against the Gaza Strip, while scores of rockets were fired back from the Hamas-run territory.
The Palestinian teenagers, aged 15 and 16, were killed when an Israeli strike hit a building they were near in the west of Gaza City, the enclave's health ministry said.
Fifteen people have been wounded across Gaza, the ministry said.
The flare-up came after the occupying army shot and killed two Palestinians, including a teenager, and wounded hundreds of others in border clashes on Friday, the latest in months of protests.
The Israeli raids on Saturday involved the "largest daytime operation" carried out by its air force in Gaza since a war in 2014, Israel's military spokesman Jonathan Conricus told journalists.
The occupying army said dozens of strikes targeted military facilities belonging to the Gaza Strip's Islamist rulers Hamas, against which it has fought three wars over the past decade.
In the other direction "more than 60 rockets" were fired at southern Israel from Gaza, the Israeli military said, of which "approximately 10 rockets were intercepted".
On Saturday the Israeli military said it was conducting strikes against Hamas "in response to the terror acts instigated during the violent riots that took place along the security fence" the day before.
Among the main targets was the "Hamas Battalion HQ in Beit Lahia, which includes urban warfare training facilities, (a) weapon storage warehouse, training compounds, command centres, offices and more", the Israeli army said in a statement.
"A weapons manufacturing site and storage facilities housing various types of weapons, including Hamas' naval capabilities" were also hit, the statement added.
The occupying army said air strikes carried out in the morning hit "complexes used to prepare arson terror attacks and a Hamas terror training facility".
Hamas spokesman Fawzi Barhoum said the group was responsible for Saturday's barrage against Israel and that it was carried out "in response to the Israeli air strikes".
"The protection and the defence of our people is a national duty and a strategic choice," Barhoum said.
Palestinians in Gaza have for months been demonstrating against Israel's decade-long blockade of the territory and in support of their right to return to lands they fled or were driven from during the war surrounding the creation of Israel in 1948.
In the wake of the ‘Great March of Return’ demonstrations, which started on 30 March, Gaza’s already overstretched health sector has been struggling to cope with the mass influx of casualties.
At least 140 Palestinians have been killed and thousands injured by Israeli occupation forces during the protests near the border with Israel.
Israel has maintained a crippling blockade on Gaza which it argues is necessary to isolate Hamas.
The blockade is worsening humanitarian conditions in Gaza, which human rights advocates have described as collective punishment of the Palestinians living in the strip.
The Gaza Strip faces an unprecedented humanitarian crisis, caused by over 10 years of Israeli blockade, alongside an internal Palestinian divide, which worsened in 2017, according to the United Nations Office for the Coordination of Humanitarian Affairs (OCHA).
*This story was edited by Ahram Online.