Remains of American Israeli hostage among 3 bodies returned by Hamas, IDF says

Israeli forces struck 30 "terrorist targets" in Gaza from Tuesday into Wednesday before announcing the ceasefire was back in effect, the Israel Defense Forces said in a statement.

The IDF conducted strikes in Khan Younis and in northern Gaza, it noted in separate statements.

At least 91 Palestinians were killed in these strikes across Gaza, according to Gaza Civil Defense.

The IDF also announced that one of its reservist soldiers was killed in an attack in Rafah on Tuesday. Israel cited the killing as one of the reasons why it conducted strikes on Gaza on Tuesday and Wednesday. Hamas denied involvement with the killing of the soldier.

-ABC News' Jordana Miller

The Israel Defense Forces said in a Wednesday morning statement that it had resumed adherence to the ceasefire in Gaza "following a series of significant strikes in which dozens of terror targets and terrorists were attacked."

"The IDF will continue to enforce the agreement and respond forcefully to any violation," the statement said.

The Hamas-run Civil Defence agency said that at least 91 Palestinians were killed in the renewed strikes across Gaza.

The bombardment came after one Israeli soldier was killed in an attack in the southern Gaza city of Rafah on Tuesday. Hamas denied involvement in the incident.

President Donald Trump said he backs Israel's strikes on Gaza, arguing the move was "retribution" for a reported attack on Israeli troops -- but he's said he's confident the ceasefire deal will hold.

Trump said "Israel should hit back" following strikes on Gaza after Israel accused Hamas of violating the ceasefire agreement.

Still, the president remained confident that the ceasefire would hold, repeating his threat that if Hamas is "not good, they’re going to be terminated."

"Nothing's going to jeopardize that," Trump said, referring to the ceasefire. "You have to understand, Hamas is a very small part of peace in the Middle East, and they have to behave. They're on the rough side, but they said they would be good. And if they're good, they're going to be happy, and if they're not good, they're going to be terminated. Their lives will be terminated. And they understand that."

He added, "If we have to, we'll take out Hamas very easily, and that'll be the end of Hamas. We would rather not. We made a deal with them where they were going to behave, and they have to behave. If they don't behave, they get taken out."

-ABC News' Lalee Ibssa

The International Committee of the Red Cross called Hamas' alleged staging of the discovery of a body in Gaza while Red Cross observers were in attendance on Monday "unacceptable."

The Israel Defense Forces released a video that it said shows Hamas staging the discovery of a hostage body in Gaza.

"It is unacceptable that a fake recovery was staged, when so much depends on this agreement being upheld and when so many families are still anxiously awaiting news of their loved ones," the ICRC said in the statement on Tuesday.

ICRC observers accompanied Hamas earlier this week to provide any needed technical guidance in recovery efforts, but the ICRC does not participate in searching for the deceased or in physical recovery of remains per international law.

"The ICRC is raising its concerns directly with the parties," the organization added.

Israeli authorities cited this as one of the reasons for conducting strikes in Gaza on Tuesday, threatening the fragile ceasefire in place.

-ABC News' Cindy Smith