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Hani Al Madhoun was horrified when he saw a video on social media that showed his younger brother, Mahmoud, sitting in his underwear with his hands over his head on a Gaza street, as armed Israeli soldiers stood guard over him and other men.
A phone call to his other brother, Mohammed, later confirmed it was their brother in the video and that their elderly father, Omar, was also among the detainees. In all, seven of his relatives were detained at a house they had fled to in Beit Lahia, in the north of the Palestinian enclave.
“It's utter humiliation and I take this personally,” Mr Al Madhoun, who lives in Virginia, told The National.
“[Israeli troops] are in it for revenge – they are not coming for justice.”
Mr Al Madhoun said his brother owned a shop in Gaza and was not involved in politics.
“He has no political theories, he doesn’t even have an opinion. He just sells cell phones on a discount,” he said. “He is not even physically fit to be a fighter.”
He added that he has since heard that his relatives have been released, but he has not been able to speak to Mahmoud directly due to ongoing issues with connectivity in the Palestinian territory.
Images circulated on Thursday on social media and on Israeli TV showed blindfolded men sitting with their hands tied behind their backs as Israeli soldiers look on.
The images surfaced as Israel intensified its bombardment and ground invasion of the Gaza Strip, killing hundreds of civilians since last week's truce collapsed, despite US calls to do more to reduce civilian casualties.
Times of Israel reporter Emanuel Fabien posted photos on X, formerly Twitter, of men stripped down to their underwear in Beit Lahia, as well as in a sandy area that could be a beach. He said it was “unclear” if the men belonged to Hamas or not.
Israeli army spokesman Admiral Daniel Hagari said “we are investigating to see who is linked to Hamas and who is not”.
Asked about the images, Admiral Hagari said “terrorists were surrendering”.
Also among those thought to have been detained in the wave of arrests is journalist Diaa Al Kahlout, Gaza bureau chief for Al Araby Al Jadeed, also called The New Arab.
His colleague Layal Haddad told The National that her London-based news outlet had lost contact with Al Kahlout on Thursday. A family member first reported that he had been arrested in Beit Lahia, which the outlet later confirmed after analysing video footage.
The relative said Al Haklout was being held along with two of his brothers and that Israeli troops had taken the men from their homes, bound their hands and put them on the street without any clothes on.
The relative said soldiers had forced women to go to Kamal Adwan Hospital and drove the detainees to an unknown location.
Haddad said Al Kahlout had moved to Beit Lahia at the start of the war and stayed there because he was worried that his disabled daughter and elderly mother would not be able to move elsewhere.
She also said Israeli forces burnt down Al Kahlout’s family home after he was detained.
“We are doing everything we can for his release, co-ordinating with Reporters Without Borders and the Committee to Protect Journalists,” she added.
“Our colleague is a well-known figure in Gaza. We believe his arrest is part of the continuing targeting of journalists to prevent them from reporting”.
On Friday, the Israeli military said it had struck more than 450 targets in Gaza by land, sea and air. The Palestinian Health Ministry in Gaza says 350 people were killed on Thursday alone.
Officials say more than 17,000 Palestinians have been killed in Israel’s military campaign and thousands remain missing under the rubble of collapsed homes and buildings.