At least 25 Palestinians were killed in Israeli strikes across the Gaza Strip on Wednesday, the Hamas-run health ministry has said, in what was one of the deadliest days since the ceasefire came into effect five weeks ago.

Ten people were killed when a ministry of religious endowments building in the eastern Zeitoun neighbourhood of Gaza City was hit, according to rescuers.

Israel's military said it struck 'Hamas terrorist targets' after gunmen opened fire towards an area where its soldiers were operating in the southern city of Khan Younis in violation of the ceasefire deal.

Hamas questioned the claim and denounced what it said was a 'dangerous escalation' that could jeopardise the ceasefire.

The flare-up of violence comes after the UN Security Council passed a resolution that endorsed US President Donald Trump's Gaza peace plan to end two years of devastating war.

Mahmoud Bassal, a spokesman for Gaza's Hamas-run Civil Defence agency, told the BBC that Israeli air, drone and artillery strikes hit several locations in Gaza City and Khan Younis shortly after sunset on Wednesday.

The attacks marked a sharp escalation after several days of relative calm, he said.

The Civil Defence reported that the strike in Zeitoun caused severe damage to the religious endowments ministry's building and surrounding structures, and posted a video showing its rescue workers appearing to find two people buried under rubble.

Photos published by the Anadolu news agency meanwhile showed the bodies of three young children reportedly recovered from the scene.

In a separate incident in Gaza City, one person was killed and several others were wounded when a drone struck a group of people at Shejaiya junction on Salah al-Din Street, Gaza's main north-south road, according to Mr Bassal.

Israel's Defense Forces (IDF) stated that they began striking Hamas targets across Gaza in response to gunfire towards soldiers, reinforcing the tense atmosphere following the ceasefire.

As tensions remain high, the prospect for sustained peace efforts appears fragile, particularly with ongoing concerns from the international community about Hamas’s commitment to disarmament.