With fighting raging around Khan Younis and in the north of Gaza, a video has emerged on social media showing dozens of Palestinian men detained by Israel.
The footage, verified by the BBC, shows them stripped to their underwear, kneeling on the ground and being guarded by Israeli soldiers.
The men are thought to have been arrested in Beit Lahia, in the far north of the Gaza strip.
The BBC has been told some of the men have since been released.
One of the men identified as having been detained is a well-known Palestinian journalist, leading his employers to accuse Israel of carrying out "invasive searches and humiliating treatment" of civilians.
Asked about the video, a spokesman for the Israeli government told the BBC the men detained were all of military age and had been "discovered in areas that civilians were supposed to have evacuated weeks ago".
In the video, dozens of men are lined up on a pavement and appear to have been told to remove their shoes, which are scattered across the road. Israeli soldiers and armoured vehicles are standing guard over them.
Other images show them being transported in military trucks. In the Israeli media, the captives are being described as Hamas fighters who have surrendered.
Another image - which has not yet been verified by the BBC - shows men blindfolded, kneeling in what appears to be a large pit of bulldozed sand.
The Israel Defence Forces (IDF) has not directly commented on the images, but spokesman Daniel Hagari said on Thursday that "IDF fighters and Shin Bet officers detained and interrogated hundreds of terror suspects".
"Many of them also turned themselves in to our forces during the past 24 hours. The intelligence coming out of their interrogations is utilised to continue the fighting."
On Friday, Israeli government spokesman Eylon Levy told the BBC the men had been detained in Jabalia and Shejaiya in northern Gaza, which he described as "Hamas strongholds and centres of gravity".
"We`re talking about military age men who were discovered in areas that civilians were supposed to have evacuated weeks ago," he said.
Mr Levy added that they would be questioned to "work out who indeed was a Hamas terrorist and who is not".
He emphasised the detained men had been found in areas where Israeli forces had engaged in "close-quarter combat" with Hamas. They had been "deliberately disguising themselves as civilians" and operating from civilian buildings.
The BBC has spoken to a man who says 10 of his cousins were part of the group detained by the Israeli army on Thursday in Beit Lahia.
The man - who wishes to remain anonymous over safety concerns - told BBC Arabic`s Ethar Shalaby that IDF soldiers entered the area and used microphones to order the men from their homes and UN relief agency (UNRWA) schools.
The IDF ordered women in the area to go to a nearby hospital and later threated to shoot them if the men did not come out of their homes, he said.
The man said seven of his cousins have since been released and have returned home, but added he does not know about the fate of the three who remain in Israeli detention.
In a post on social media, the Palestinian ambassador to the UK described the footage as "savage images of Israeli occupation forces detaining and stripping civilians taken from a UN shelter".
"This evokes some of humanity`s darkest passages of history," Husam Zomlot said.
A picture of the men, verified by the BBC, has been circulating on social media
Palestinian journalist, Diaa al-Kahlout, a correspondent for al-Araby al-Jadeed, has been identified among those who were in the video of the detainees.
The Arabic language news outlet, which also publishes in English under the name the New Arab, said Mr al-Kahlout had been arrested along with his brothers, relatives and "other civilians" by Israeli forces in Beit Lahia.
Al-Araby al-Jadeed has condemned what it describes as the "humiliating" detention of Mr al-Kahlout on Thursday.
It added that soldiers forced the men to remove their clothes and "subjected them to invasive searches and humiliating treatment upon their arrest, prior to transporting them to undisclosed locations".
The outlet "urges the international community, journalists` rights defenders and watchdogs, and human rights bodies to denounce this ongoing assault" by Israel on journalists in the territory.
The BBC has asked the IDF about Mr al-Kahlout`s reported detention.
