On Sunday evening, Israelis whose family members have been taken hostage by Hamas militants held a news conference, with the eyes of the world focused on their grief. “My two little girls, they’re only babies. They’re not even five years old and three years old,” said Yoni Asher, who recounted seeing video of gunmen seizing his wife and two daughters. Another father, Uri David, said he had spent 30 minutes on the phone with his daughters, Tair and Odaya, before a sudden frenzy on the other end of the line cut them off. “I heard shooting, shouting in Arabic, I told them to lie on the ground and hold hands,” David said, adding he was now unaware of their fate. “I am asking for the whole world to see what I am going through. We have to bring the children home – and as fast as possible,” he said. About 100 Israelis, military and civilians, are believed to have been taken into Gaza after the surprise attack by the militant group Hamas on communities in the south of Israel. On Monday, Hamas claimed that four hostages and their captors had been killed in Israeli airstrikes since Sunday, Reuters reported. A second Palestinian militant group, Islamic Jihad, said it was also holding more than 30 captives. An Israel Defence Forces (IDF) spokesperson has said that “it is unprecedented in our history that we have so many Israeli nationals in the hands of a terrorist organisation”. Israeli authorities have been cautious in revealing the exact numbers of people taken. In a late-night update, IDF spokesperson Lt Col Jonathan Conricus said: “I can only say that we are talking about many, many Israelis … Women, children, infants, elderly and even disabled people.” A reservist brigadier-general, Gal Hirsch, who was appointed by the prime minister, Benjamin Netanyahu, to lead on kidnapped and missing Israelis, said on Monday: “We are creating a full situational picture and are working at full strength to create an effective system.” His message to families of the missing continued: “We have heavy missions ahead of us, and I am with you in the campaign to bring all the missing and kidnapped back home to Israel.” Meanwhile, Qatar was reported to be attempting to broker an agreement for Hamas to release Israeli women and children in exchange for Israel freeing 36 Palestinian women and children from Israeli prisons, Reuters reported. For many families, the news that their loved ones had been taken hostage was announced through videos filmed by Hamas and then shared on social media and through WhatsApp groups. It was a video of her two daughters sitting on a mattress in captivity that alerted Mayyan Zin to their disappearance. She then found other clips online of gunmen entering her ex-husband’s home, her terrified daughters weeping behind him. Nitzan Eli Akin’s family members Noam, 48, Dikla, 51, and Ella, were all seized from the same community as well. His last contact with them was at 10.30am on Saturday, when they messaged to say militants were close by. “There is some blood on their clothes but they seem in OK health. We are just begging for anyone to help us return them safely,” he said. Israeli officials announced late on Sunday that at least 260 bodies had been discovered at the site of the Supernova music festival that took place by a desert kibbutz near Gaza this weekend. Dozens more remain missing and are thought to have been taken as hostages. Videos posted on social media showed hundreds of attendees running from gunmen as Hamas militants pursued them on motorbikes. Among them, the capture of the Israeli woman Noa Argamani has become an emblematic image of the short and brutal conflict, beamed around the world into news broadcast and on to front pages. In the video, Argamani pleads for her life as she is separated from her partner and driven away on a motorbike by two Hamas fighters. Her identity was confirmed by her partner’s brother, who saw her and his brother in the videos online. “I saw Noa in the video scared and frightened, I can’t imagine what’s going through her mind at all – screaming in panic on a motorcycle,” he said, speaking to Israeli media. In a separate video, another woman who attended the festival is paraded through Gaza apparently unconscious. Her cousin identified her as German-Israeli national Shani Louk to the Washington Post. Several foreign nationals are feared to have been taken hostage as well. Mexico’s government announced that two citizens – a man and a woman – had allegedly been taken. At least three Brazilian nationals are also missing, according to Brazilian officials. An unknown number of Americans are also among the hostages, the Israeli ambassador to the US said on Sunday. The IDF has said Israel would act to free the hostages, but analysts have warned that trying to rescue all those Hamas said were now being held in different locations could jeopardise their lives. “The cruel reality is Hamas took hostages as an insurance policy against Israeli retaliatory action, particularly a massive ground attack,” said Aaron David Miller, a senior fellow at the Carnegie Endowment for International Peace. The families of those missing have implored Israel’s government and the international community to look beyond politics. “It’s not about politics … It’s really about humanity. The kids are there … please help them,” said Malki Shmetov, whose son is missing. On Sunday evening, Merav Leshem Gonan, whose daughter is also among the hostages, recounted a phone conversation in which her daughter had begged for help. “We are on the phone to her and I’m saying: ‘We love you it’s OK, we’re trying to find a way to take you out of there.’ And I know I’m lying because I don’t have answers.”