The families of hostages held in the Gaza Strip kicked off a 24-hour rally in Tel Aviv Saturday night, calling on the government to bring their loved ones home after 100 days spent in Hamas captivity.

Thousands of people poured into “Hostages Square” at Tel Aviv — a central plaza opposite Israel’s Defense Ministry that has served as a gathering point for the campaigners.

Hamas and other terrorists from Gaza captured some 250 people during its deadly October 7 attack on southern Israel, while killing some 1,200 other people, most of them civilians. Sunday marks the 100th day in captivity for the hostages.

More than 100 hostages were released during a temporary truce in November, but 132 remain held in Gaza including the remains of about two dozen who died or were killed.

“We were here on day 50 and spoke on this stage. We are not going to speak again in 50 days. It’s time to bring them back. Now! Bring them back!,” said Ronen Neutra, the father of Omer Neutra, an Israeli soldier who was taken. “They are being held in terrible conditions. They are starving. They are dying.”

There has been little visible progress toward a new deal to release hostages. Their families are using the 100-day mark for a new appeal to the government to prioritize bringing home the abductees. Some have said the government has not done enough.

Israel said Saturday that it had brokered a deal with mediator Qatar to deliver badly needed medicines to the hostages with the help of the International Committee of the Red Cross. There was no immediate sign that the deal was being implemented.

Near the rally in support of the hostages, anti-government demonstrators calling for new elections to be held blocked a major Tel Aviv highway, clashing with police who made arrests and tried to push the crowd back. Other protesters advanced toward Prime Minister Netanyahu’s private residence in the coastal town of Caesarea, calling for his dismissal from office.

Many of the protesters at Tel Aviv stayed out all night. The crowd listened to a recorded message from President Macron of France, and heard from the American ambassador to Israel, Jacob Lew. Messrs. Lew and Macron pledged to exhaust every effort to bring the remaining hostages home.

“Today, as we mark 100 days since hundreds of innocent men, women and children were violently seized from Israel, we join as one in demanding their release,” Mr. Lew said.

In previous exchanges of hostages for Palestinian prisoners, nearly all freed on both sides were women and minors. Now, 111 men, 19 women and two children remain in Gaza.