"In response to the blatant violation of the ceasefire agreement earlier today (Sunday), the IDF (Israeli army) has begun a series of strikes against Hamas terror targets in the southern Gaza Strip", the military said in a statement.

Under the terms of the agreement, Hamas and its allies committed to releasing all remaining hostages they seized on October 7, 2023. They have so far released all 20 surviving hostages, but have returned only 12 bodies of the 28 dead hostages they still hold, blaming difficulties in locating them under the rubble.

Besides failing to return all the hostages, Israel accuses Hamas of targeting its troops in areas of the Gaza Strip where they are allowed to be stationed under the deal, a claim that Palestinian militants reject.

An Israeli military official said that a first wave of strikes on Sunday morning was in retaliation for at least three attacks against its forces.

According to the official, the army responded to "at least three incidents in which Hamas fired towards our troops standing behind the yellow line in the agreed-upon positions," referring to the line of withdrawal of the Israeli army under the terms of the ceasefire.

In two incidents in Rafah in the southern Gaza Strip, Hamas allegedly opened fire and launched a rocket-propelled grenade against Israeli troops, some of whom were engineering forces "operating to dismantle terrorist infrastructure in southern Gaza."

The official said that troops were stationed in areas behind the yellow line where the Israeli military is allowed to manoeuvre under the terms of the truce.

In a separate incident in Beit Lahia in the northern Gaza Strip, Palestinian militants crossed the yellow line into Israel-controlled areas and were "eliminated in a precise strike," the military official said.

Hamas denied the accusations it had attacked Israeli forces, saying it was adhering to the truce and that Israel was devising "flimsy pretexts" to resume the war.

Palestinian witnesses told AFP that clashes erupted in Rafah, in an area still held by Israel, between Hamas and a local Palestinian gang known as Abu Shabab, supported by Israel.

Following the strikes, Prime Minister Benjamin Netanyahu met Defence Minister Israel Katz and the heads of the Shin Bet and Mossad security agencies, and "directed that strong action be taken against terrorist targets in the Gaza Strip," according to a statement from his office.