Some of the activists detained while trying to reach Gaza by sea have returned to their home countries to describe mistreatment at the hands of Israeli guards, claims that Israel denies.

Some 450 activists were arrested as Israeli forces intercepted the Global Sumud Flotilla, a fleet of 42 boats seeking to break Israel's naval blockade of Gaza and deliver a symbolic amount of aid to the famine-stricken territory. Those detained between Wednesday and Friday were brought to Israel, where many remain in prison.

Hundreds of thousands of people across several European cities marched Sunday in support of Palestinians and an aid flotilla 's attempt to reach Gaza.

Israeli and Hamas officials are set to hold indirect talks at an Egyptian resort Monday on a U.S.-drafted peace plan to end the ruinous war in Gaza on the eve of its second anniversary.

Many uncertainties remain about the plan presented by U.S. President Donald Trump last week, including the disarmament of the militant group — a key Israeli demand — and the future governance of Gaza. Trump is seeking an agreement on Gaza, which he has indicated could pave the way for a revamped Middle East peace process that could reshape the region.

A senior Hamas official on Sunday said the Palestinian militant group is eager to reach an agreement to end the war and implement a prisoner swap with Israel, as negotiators converge in Egypt for talks.

Israeli Defense Minister Israel Katz said on Sunday that the military's offensive in Gaza City has so far displaced approximately 900,000 Palestinians.

Israeli and Hamas negotiators were converging on Cairo Sunday for talks to end nearly two years of war in Gaza, with Israel's leader expressing hope that hostages held in the devastated territory could be released within days.

Turkey said 36 of its citizens were expected to return home via a special flight on Saturday afternoon, after Israel intercepted a Gaza-bound aid flotilla.

Israel's army said Saturday that it would advance preparations for the first phase of U.S. President Donald Trump's plan to end the war in Gaza and return all the remaining hostages, after Hamas said it accepted parts of the deal while others still needed to be negotiated.

Hamas said Friday that it has accepted some elements of U.S. President Donald Trump's plan to end the war in the Gaza Strip, including giving up power and releasing all remaining hostages, but that others require further consultations among Palestinians.

The statement came hours after Trump said that Hamas must agree to the deal by Sunday evening, threatening an even greater military onslaught nearly two years into the war sparked by the Oct. 7 attack into Israel. There was no immediate response from the United States or Israel, which is largely shut down for the Jewish Sabbath.

U.S. President Donald Trump on Friday issued an ultimatum to Hamas of 2200 GMT Sunday to accept his Gaza peace deal or face "all hell."

The Palestinian militants have until "Sunday Evening at SIX (6) P.M., Washington, D.C. time," Trump posted on his Truth Social platform.