'Nowhere to go': Ordinary Palestinians live in fear as Israel retaliates against Hamas

When the Palestinian militant group Hamas launched an attack on Israel Saturday morning, Palestinians living in the besieged strip had mixed feelings.

Some celebrated, taking pride in what they perceived as a victory against Israel. Others, however, were afraid, dreading a deadly retaliation.

The militant group's unprecedented incursion prompted vows of retribution from Israeli Prime Minister Benjamin Netanyahu, who declared on Saturday that his country was at war, pledging a "mighty vengeance for this black day."

Israel's Minister of Strategic Affairs Ron Dermer told CNN's Dana Bash on Sunday that more than 600 people have been killed in Israel, and that the death toll is likely to rise.

Israel Defense Forces (IDF) spokesperson Rear Adm. Daniel Hagari said Sunday that Israel destroyed around 800 targets in Gaza, including what he described as launching pads used by Hamas.

At least 413 Palestinians have been killed, including 78 children, the Palestinian Ministry of Health in Gaza said.

No strangers to war with Israel, many Gazans are sheltering in their homes, with the vast majority lacking access to bunkers. The territory is one of the most densely populated places on earth, where some 2 million people live in an area of 140 square miles.

Those who venture out do so only to complete essential errands, or to look for their missing in the carnage of Israeli strikes. The streets are damaged and covered with rubble, and the air smells of dust and gunpowder.

Salim Hussein, 55, lost his home when his building was targeted in an Israeli airstrike. He lived on the first floor and told CNN that he and his family were given warnings by Israel just moments before the building was struck.

Hussein said he did not know why the tower was struck. He had moved in with his family just five months ago.

"We left (the tower) only with the clothes we had on," he told CNN, adding that he and his family now have nothing left and nowhere to go.

Following Hamas' incursion, Palestinians were also barred from leaving Gaza through Erez crossing, which has become the site of a battle between Hamas and Israeli forces.

Netanyahu declared Saturday that Israel will be stopping the supply of "electricity, fuel and goods" into the Gaza Strip, although IDF spokesperson Lt. Col. Richard Hecht said Sunday only electricity had been cut. Since then, power is only available for an average of four hours per day, down from the usual eight hours. Israel supplies the majority of Gaza's electricity.

Internet connectivity has also been choppy.

The Gaza Strip has been almost completely cut off from the rest of the world for nearly 17 years.

Governed by Hamas since 2007, the enclave is under strict siege by Egypt and Israel, which also maintains an air and naval blockade on Gaza. It has been described by Human Rights Watch as the "world's largest open-air prison."

Gazans have seen Israeli strikes ravage the strip on several occasions since Israeli forces withdrew from the territory in 2005. Fighting regularly takes place between Israel and Palestinian factions in Gaza, including Hamas and Islamic Jihad.

Overnight, Israel struck down at least 10 towers in Gaza that it said were used by Hamas, Hagari said Sunday, adding that tens of thousands of Israeli soldiers are operating on the ground around the Gaza Strip.

The IDF on Sunday said it is now focusing on taking control of the Gaza Strip, and urged civilians there to leave residential areas near the border immediately for their safety as Israeli military operations continued to target Hamas.

But most Gazans have no way of fleeing the besieged enclave. All crossings out of the territory are shut, with the exception of the tightly controlled Rafah crossing with Egypt.

Hani El-Bawab, 75, said he and his family of four had been up all night, fearing airstrikes. The tower adjacent to his home was hit by Israel overnight, collapsing onto his own house and rendering him and his family homeless.

"I don't know what to do," El-Bawab said. He now lives on the street, while his wife stays with an acquaintance.

Palestinians in Gaza, he said, are living in "panic and fear," preparing each moment for a bomb to crash into a building. "I just want a house to live in with my kids. I just want shelter," he told CNN.

Nevertheless, he doesn't regret Hamas' attack on Israel. "Every time, they (Israel) are the ones who attack us," he said. "This time, the (fighters) are the ones who went in."

CNN's Nadeen Ebrahim contributed to this report.