An Irish-based orthopaedic surgeon, whose brother was killed in Gaza last year, said four of his sister’s children were killed and his sister was badly wounded in Israeli missile strikes on the Palestinian territory.
The children were among casualties in the attacks on dozens of targets across Gaza.
More than 400 people were killed in overnight Israeli air strikes, the Palestinian health authorities said. The attacks have shattered a fragile ceasefire in place since January 19th.
More than 660 people were injured, the authorities said.
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Dr Mahmoud Abumarzouq, who works as a surgeon in Our Lady’s Hospital in Navan, Co Meath, said he was awaiting news on the condition of his sister Seham, who was in intensive care.
Her teenage boys, Mohamed and Refat, were killed alongside her daughters, Dinna and Noor, whose three-day-old baby daughter Yaqout was badly injured and was taken to intensive care.

Dr Abumarzouq’s sister and children were staying with relatives in the south of Rafah when the attack occurred. They had moved to this location as their own home had been destroyed by missile attacks. Seham’s two other children are in Egypt and safe.
This is the latest tragedy to befall the family in Israel’s attacks on Gaza.
Seham’s husband Osama died last year in a missile attack. Dr Abumarzouq also lost his 29-year-old brother Ahmed Mahmoud when an Israel bomb hit a refugee camp in Rafah.
“I had a bad feeling when I woke up this morning and then saw all the missed calls and messages from family members,” Dr Abumarzouq said.
“Initially they thought that my sister was dead, but I’ve since discovered that she was found alive but very badly injured and is now in intensive care.”

Other members of his sister’s family were also killed in the attack.
“Her family is all gone. Ten of her in-laws were killed as well last night; all of her in-laws were wiped out. There were no survivors on that side of her family,” he said.
“I just talked to my sister yesterday and they were so happy with the new baby. They were a little worried about getting baby food, but her arrival was a little bit of hope to cling to.
“Now they are gone and the tiny tot is clinging for her own survival.”
Dr Abumarzouq said his father was “destroyed” by the death of his daughter and four grandchildren.
“He buried my brother last year and will now be burying the little ones. It is the worst thing he has had to do in his life,” he said.
The January 19th ceasefire that had halted the fighting in the Israel-Hamas conflict had initially left him hopeful for the future.
“I could breathe a little lighter when the ceasefire was called but now the unimaginable has happened,” he said.
“There are no words. Yes, my family and children are safe here, thankfully, but our souls are in Gaza and my heart has been completely shattered in grief and sorrow today.
“There is no use in words any more. No one is helping the Palestinians. They are being massacred. What is going on isn’t human.”
Speaking in New York, Tánaiste Simon Harris said the scenes overnight in Gaza were “horrific”.
“The impact of the strikes is utterly devastating on a population that has already endured unimaginable pain and catastrophe. We have seen strikes that have killed hundreds of civilians, including, disproportionately, children and we really need an immediate cessation of violence.
“We need an intensification of that process. We need the hostages released. What we don’t need is a return to the attacks on the civilian population of Gaza and the scenes we have seen overnight.”
Mr Harris said Ireland was trying to get aid to the civilian population in Gaza.
“We in Ireland have Irish Aid sitting in trucks in Jordan. We desperately want to get that Irish aid into the civilian population – food, shelter, we have enough for 6,000 people in the Irish trucks alone.
“Not only is that aid not getting in, we are now seeing indiscriminate attacks on the civilian population and should be condemned by all.”