Hostages abducted by Hamas gunmen during the Oct 7 attack on Israel are handed over to the International Red Cross as part of a hostages-prisoners swap between Hamas and Israel amid a cease-fire, in the Gaza Strip, Nov. 29, 2023. [Reuters]

Hamas militants freed more Israeli hostages Wednesday, the sixth day of a truce between the warring parties, while negotiators worked to extend the pause in fighting and free even more hostages in exchange for Palestinians held in Israeli jails.

With the cease-fire set to formally end Thursday morning, top officials from Qatar, the United States, Egypt and Israel were meeting in Qatar to discuss how, and for how long, to extend the halt in fighting to allow further swaps of hostages and prisoners.

U.S. Secretary of State Antony Blinken, scheduled to travel to Israel on Thursday, told reporters in Brussels that an extended truce "means that more hostages will be coming home, more [humanitarian] assistance will be getting in" to help displaced Palestinians in Gaza.

"Clearly, that's something we want," Blinken said. "I believe it's also something that Israel wants. They're also intensely focused on bringing their people home."

Qatar told CNN it was "very optimistic" the truce would be extended, likely under the same terms as the first six days, with about three times as many Palestinians held for various offenses in Israeli jails being freed compared with the number of hostages being released by Hamas, which has been designated a terrorist organization the U.S., U.K, European Union and others.

One Israeli official told The Washington Post that the truce could be extended by two or three days, but a further cessation in fighting would not "lead to a permanent cease-fire."

The official said the "goal of removing Hamas from its rule in Gaza" remained the key objective for the Jewish state after Hamas' surprise October 7 attack on southern Israel killed about 1,200 people and allowed it to capture about 240 hostages. In response, an Israeli aerial bombardment and ground invasion of Gaza has killed more than 15,000 people, according to the Hamas-controlled Gaza Health Ministry.

The Israel Defense Forces said Wednesday that Lieutenant General Herzi Halevi, the Israeli army's chief of staff, had approved plans for "the continuation of the fighting" in Gaza after the pause ends.

Among those Hamas freed Wednesday were two Russian-Israeli citizens - Elena Trupanov, 50, and Irina Teti, 73 - according to the Israeli government.

Hamas said Wednesday that three hostages - Kfir Bibas, 10 months; his brother Ariel, 4; and their mother, Shiri Silberman Bibas - had been killed at some undisclosed time during the Israeli bombardment of the Gaza Strip. The Israeli army said it was investigating the Hamas claim.

The original Israel-Hamas truce called for four days of Israel pausing its campaign to eradicate the Hamas militant group, with Hamas releasing 50 hostages it seized during an attack on Israel last month and Israel setting free 150 Palestinian prisoners. The pause also allowed for increased humanitarian aid to reach the battered Gaza Strip.

A two-day extension was added under the terms of Hamas releasing 10 more hostages per day and Israel freeing additional prisoners.

The Israeli military said 12 hostages who had been held in Gaza - 10 Israelis and two foreign nationals - were driven to Israel late Tuesday, with more on Wednesday night. In turn on Tuesday, Israel freed 30 Palestinian prisoners - 15 women and 15 young men from a West Bank prison and a Jerusalem detention center - according to the Palestinian Prisoners Club, a semiofficial organization.

The six-day truce has brought Gaza its first respite after six weeks of intensive Israeli aerial bombardment and the ground offensive prompted by the Hamas attack.

With the Israeli bombardment of the Gaza Strip, the United Nations estimated 1.8 million of Gaza's 2.3 million people had fled their homes, with many staying in overcrowded shelters. Shelter Network, a U.N.-led aid consortium, said in a report last Friday that more than 60% of Gaza's housing stock had been damaged or destroyed.

The World Health Organization warned Tuesday about the high risk of "explosive outbreaks of infectious diseases" amid the overcrowded conditions and the disruption of health, water and sanitation systems in Gaza.

The U.N. Security Council was due to hold a meeting Wednesday focused on the Israel-Hamas conflict.