(NewsNation) — International negotiations have intensified to secure the release of more than 200 people kidnapped in the wake of Hamas’s terrorist attack against Israel on Oct. 7.

On Monday, up to 50 hostages may have been freed, The Guardian reports. Still, Israel has intensified its strikes on Gaza, and experts warn negotiations are likely to be the only way to obtain hostages.

It comes amid the release of two elderly women, 79-year-old Nurit Cooper and 85-year-old Yocheved Lifshitz, who were freed late Monday, leaving behind around 220 hostages in the hands of Hamas.

Lifshitz said she’d been beaten by militants as she was taken into Gaza on Oct. 7, but was then treated well during her two-week captivity in the Palestinian enclave.

“I’ve been through hell, we didn’t think or know we would get to this situation,”  Lifshitz told reporters, seated in a wheelchair outside the Tel Aviv hospital where she was taken following her release.

Looking frail, Lifshitz said she had been put on a motorbike and driven from her kibbutz into nearby Gaza.

“When I was on the bike, my head was on one side and the rest of my body on the other side. The young men hit me on the way. They didn’t break my ribs but it was painful and I had difficulty breathing.”

Once in Gaza, she said her captors took her into tunnels that she compared to a spider’s web, and treated her well.

Lifshitz said a doctor had visited her and made sure she and other hostages received the same sort of medicines they had been taking in Israel.

She said the Israeli military had not taken the threat of Hamas seriously enough, and that the costly security fence meant to keep militants out “didn’t help at all”.

Lifshitz’s husband, Oded, and Cooper’s husband, Amiram, are believed to still be held by Hamas, Israel said.

The Biden administration has said at least 10 American citizens are unaccounted for and has not confirmed that they are being held by Hamas.

Among the more than 200 hostages are children who are just a few months old, young women and men, the elderly and Holocaust survivors. Efforts to secure their release include diplomatic efforts from Israel, the U.S. and Qatar, which has open lines of communication with Hamas through the terrorist group’s political office in Doha. 

The U.S. is working “hour by hour” on efforts to recover hostages, National Security Council spokesperson John Kirby told reporters Monday, but he did not speak directly to reports that the White House is pressuring Israel to delay its ground incursion into Gaza to allow more time for hostage recovery and for humanitarian aid to reach Palestinians.

The U.S. is asking “tough questions” about Israel’s military objectives, Kirby said, and has sent over military officers to Israel “to share some perspectives from their own experience and to ask the hard questions,” over its military objectives. 

He added: “We have, since the beginning of the conflict in the early hours, maintained a level of communication with our Israeli counterparts to ascertain their intentions, their strategy, their aims, to see what their answers are.”

Israel Defense Forces spokesman Rear Adm. Daniel Hagari told reporters Monday that the number of hostages includes a not-insignificant number of foreign nationals, the Times of Israel reported.

When asked whether the ground operation is being delayed to allow more time for attempts to secure the release of hostages, the Times of Israel quoted Hagari as saying, “We are working in all ways to free the hostages and bring them home.”

Hamas, in a message posted to Telegram on Saturday, said that it had communicated to Qatar it was ready to release two hostages, whom it referred to as Nurit Yitzhak, likely referring to Cooper, and Lifshitz “due to compelling humanitarian reasons.” It accused the Israeli government of refusing to receive them.

Kirby, at the White House on Monday, said the U.S. does not take anything Hamas says at face value and called for the immediate and unconditional release of all hostages. 

Reuters and The Hill contributed to this report.