Israel's army on Sunday denied claims from Gazan authorities that an Israeli strike killed a pregnant Palestinian mother and her baby, saying errant Hamas friendly fire was to blame for the deaths.
"The terror organisations' propaganda at its finest," Israeli army spokesman Ronen Manelis claimed on Twitter, despite official confirmation from authorities in Gaza.
"The mother and girl they're claiming in Gaza that were killed in an (Israeli) attack were killed by Hamas use of weapons," he added, without providing further details.
Another Israeli military spokesman, Jonathan Conricus, told journalists later that based on intelligence "we are now confident" that the deaths were not due to an Israeli strike.
"Their unfortunate death was not a result of (Israeli) weaponry but a Hamas rocket that was fired and exploded not where it was supposed to," he said.
But the Gazan health ministry said on Saturday that Falestine Abu Arar, 37, and her 14-month-old daughter were killed by an Israeli airstrike that hit their home.
A ministry spokesman told AFP she was the mother of the baby who died in the same incident earlier as Israel carried out strikes in response to some 200 rockets fired from Gaza.
Khaled Abu Qleiq, 25, was hit and killed by an Israeli strike in northern Gaza, while another Palestinian was killed earlier by Israeli raids.
An Israeli army spokeswoman said the military did not have any information on the incident involving the baby. The army said earlier it was targeting only military sites.
Israel said around 200 rockets were fired from Gaza and its air defences intercepted dozens of them.
One woman was seriously injured in a rocket strike on the Israeli city of Kiryat Gat, some 20 kilometres from the Gaza border, police said.
Police said a man was also hospitalised in the city of Ashkelon and spoke of other injuries without providing details.
As the exchange of fire continued, Israeli Prime Minister Binyamin Netanyahu held consultations with security chiefs.
A statement from Hamas ally Islamic Jihad claimed responsibility for at least some of the rocket fire and said it was prepared for more if necessary.
Its armed wing distributed a video showing militants handling rockets and threatening key Israeli sites, including Ben-Gurion international airport near Tel Aviv.
A source in the group said Egypt was engaged in discussions to calm the situation, as it has done repeatedly in the past.
The European Union called for an immediate halt to rocket fire from Gaza.
The escalation in violence follows deadly clashes along the Gaza border on Friday.
Four Palestinians, including two Hamas militants, were killed after two Israeli soldiers were wounded in a shooting during weekly protests near the border fence.
A ceasefire between Israel and Hamas brokered by Egypt and the United Nations had led to relative calm around Israel's April 9 general election.
Palestinians have participated in regular demonstrations along the Gaza border for more than a year calling on Israel to ease its crippling blockade of the enclave.
At least 271 Palestinians have been killed by Israeli fire since the protests began in March 2018, the majority along the border.
The results of a UN investigation released at the end of February found that Israel may have committed crimes against humanity in responding to the border protests, as snipers "intentionally" shot civilians including children, journalists and the disabled.
Agencies contributed to this report.
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