Intense bombing in northern Gaza as Israeli military says ground forces expanding operations on besieged enclave.

An extended series of large explosions on lit up the sky over Gaza City after nightfall on Friday, and an Al Jazeera correspondent said northern Gaza was being pounded by air raids and artillery.

The Palestine Red Crescent Society said it had completely lost contact with its operations room in Gaza and all its teams operating on the ground.

Israeli military spokesman Daniel Hagari said Israel increased air raids “in a very significant way” and that ground forces were “expanding their activity” in Gaza.

He told residents of Gaza City to move south on Friday night, as Israeli escalating Israeli attacks battered the strip.

“In the last two hours, we could hear intensive air strikes and intensive artillery shells at the same time, which is something unusual – which means the strength of the fire is much more than in the previous days,” said Al Jazeera’s Safwat Kahlout, reporting from Gaza City.

“Today is the worst in terms of the strength of the Israeli fire, and we can hear some explosions … coming from the sea as well, specifically in the north of the Gaza Strip.

“The air strikes and the artillery shells are intensifying now in the north,” he said.

The Palestinian telecommunication company Jawwal said in a social media post late on Friday that mobile phone and internet services have been shut off.

“We don’t have any internet, we don’t have any kind of signals on our phones, we’ve become totally isolated in the territory,” Al Jazeera Tareq Abu Azzoum reported from Khan Younis in Gaza on Friday. Residents were “terrified and afraid,” he said.

The service outage comes as Palestinians brace for an anticipated Israeli ground invasion of Gaza. Israeli officials have threatened to carry out a ground assault to topple Hamas, the Palestinian armed group that governs the territory. In recent days, Israeli forces have carried out limited raids in Gaza .

Israel has bombed the strip relentlessly since Hamas launched an attack on southern Israel on October 7 that killed more than 1,400 people.

Since that attack Israel has imposed a “complete siege” Gaza, cutting access to food, water, fuel, and electricity for the enclave’s 2.3 million residents who have few options for seeking refuge.

The United Nations warned that “many more will die” as a result of Israel’s ongoing siege of Gaza, which has also caused sewage to flow into the streets.

“People in Gaza are dying; they are not only dying from bombs and strikes: soon many more will die from the consequences of (the) siege imposed on the Gaza Strip,” said Philippe Lazzarini, commissioner general for the UN agency for Palestine refugees (UNRWA).

“Basic services are crumbling, medicine is running out, food and water are running out, the streets of Gaza have started overflowing with sewage.”