DEIR AL-BALAH, Gaza Strip (AP) — The Israeli army launched a barrage of attacks in Gaza on Tuesday as tensions with Hamas grew two weeks into a fragile ceasefire, and the militant group responded by saying it would delay handing over the body of a hostage. At least seven Palestinians were killed, health officials said.

The flare-up of violence presented one of the biggest tests so far for the truce and had international mediators scrambling to prevent it from collapsing. U.S. Vice President JD Vance attempted to play down the fighting, saying he expected “skirmishes” to quickly die down.

The order from Prime Minister Benjamin Netanyahu to launch “powerful strikes” came after an Israeli official said its forces were fired upon in southern Gaza and after Hamas handed over body parts on Monday that Israel said were the partial remains of a hostage recovered earlier in the war.

Netanyahu called the return of these body parts a “clear violation” of the ceasefire agreement, which requires Hamas to return the remaining hostages in Gaza as soon as possible. Israeli officials also accused Hamas of staging the discovery of these remains on Monday, sharing a 14-minute edited video captured by a military drone in Gaza.

Israel notified the United States before launching the strikes on Tuesday, according to two U.S. officials who spoke on condition of anonymity to discuss sensitive matters.

In Gaza City, at least two Palestinians were killed by strikes, according to Rami Mhanna, the managing director of Shifa hospital, where the bodies were taken. In Khan Younis, an Israeli strike on a vehicle killed five Palestinians, including two children, according to Ahmed al-Farra, the head of pediatrics at Nasser hospital, where the bodies were taken.

Earlier in the day, Israeli troops were shot at in the southern city of Rafah and returned fire, according to an Israeli military official who spoke on condition of anonymity because there hasn’t been an official announcement yet.

In a statement, Hamas denied involvement in the gunfire in Rafah and reiterated its commitment to the ceasefire. “The violent strikes carried out by Israel across the Strip is a blatant violation of the ceasefire deal,” said the group, calling on mediators to pressure Israel to stop.

The ceasefire that began on Oct. 10 has largely held despite at least two previous flare-ups in violence.

On Oct. 19, Israel said two Israeli soldiers were killed by Hamas fire. Israel responded with a series of strikes that killed over 40 Palestinians, according to local health officials.