Hamas militants have launched dozens of rockets at Israel after Israeli air strikes killed senior commanders and felled a multi-storey building in Gaza.
At least 65 people in Gaza, including 14 children, and seven people in Israel have been killed since then.
The fighting erupted after weeks of rising Israeli-Palestinian tension in East Jerusalem which culminated in clashes at a holy site revered by Muslims and Jews.
Further violence in Israeli areas with mixed Jewish and Arab populations led to the arrests of more than 374 people on Wednesday evening, Israeli police said, and 36 officers being injured.
Palestinian militants have been firing rockets into Israel since Monday night, and Israel has responded by hitting targets in the territory.
Militants in Gaza said they had fired 130 rockets into Israel in response to an Israeli aid raid which destroyed the al-Sharouk tower in Gaza City.
Israel said it had killed senior Hamas officials in Gaza, and was also targeting missile launching sites.
The Israel Defence Forces (IDF) said on Wednesday that their strikes on Gaza were the largest since the conflict in 2014.
The child killed in the Israeli town of Sderot was named as Ido Avigal, aged six, who was caught in an attack on a block of flats.
On Thursday morning, the IDF said about 1,500 rockets had been fired from Gaza into Israeli cities since hostilities escalated at the start of this week.
On Wednesday morning an Israeli soldier was killed by an anti-tank missile fired from Gaza into Israel, authorities said, while two Israeli Arabs died in Lod when a rocket hit their car.
A Russian foreign ministry statement quoted a Hamas spokesman as saying the movement was ready for a ceasefire if Israel stopped "violent acts" in East Jerusalem and "illegal measures in respect of its native Arab residents".
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.
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 the Islamic holy month of Ramadan in mid-April.
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.
Rockets pound Israel after Gaza militants killed
Rockets pound Israel after Gaza militants killed1
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