Hours after the power plant was hit, a tall column of thick black smoke still rose from the plant's burning fuel tank. The station's shutdown was bound to lead to further serious disruptions of the flow of electricity and water to the 1.7 million people packed into the narrow Palestinian territory.
The heavy strikes were a new blow to international efforts to reach a sustainable truce in the fighting, now in its fourth week.
At least 100 Palestinians were killed Tuesday, including 26 who died in airstrikes and tank shelling on four homes, according to Palestinian health officials and the Palestinian Red Crescent. That pushed the overall death toll since the conflict began on July 8 to at least 1,156, according to Gaza Health Ministry spokesman Ashraf al-Kidra.
Israel has reported 53 soldiers and three civilians killed.
In the West Bank, a top PLO official offered a 24-hour truce Tuesday, saying he also spoke in the name of Hamas, but the Islamic militants said they want to hear from Israel first. Israeli government spokesman Mark Regev declined comment.
Israeli Prime Minister Benjamin Netanyahu on Monday warned of a "prolonged" campaign against Hamas.
But it was not clear if Netanyahu has decided to expand the Gaza war into an all-out effort to topple Hamas or planned to limit Israel's operation to the previously stated goal of ending Hamas rocket fire and destroying Hamas's sophisticated network of cross-border tunnels.
Already, the intensity and the scope of the current Gaza operation is on par with an invasion five years ago, which ended with a unilateral Israeli withdrawal after hitting Hamas hard.
On Tuesday, Israeli warplanes carried out dozens of attacks, leveling the home of the top Hamas leader in Gaza, Ismail Haniyeh, and damaging the offices of the movement's Al-Aqsa satellite TV station, a central mosque in Gaza City and government offices.
Haniyeh's house, in a narrow alley of the Shati refugee camp, was reduced to rubble but no one was hurt. Residents placed a large framed portrait of Haniyeh atop the wreckage and draped it with green Hamas flags and Palestinian national banners.
Israel has targeted several homes of Hamas leaders but none has been killed - presumably because they have kept a low profile. Haniyeh said in a statement Tuesday that "destroying stones will not break our determination."
The scene at the Gaza power plant after two tank shells hit one of three fuel tanks was daunting. "We need at least one year to repair the power plant, the turbines, the fuel tanks and the control room," said Fathi Sheik Khalil of the Gaza Energy Authority. "Everything was burned."
He said crew members who had been trapped by the fire for several hours were evacuated.
Even before the shutdown, Gaza residents only had electricity for about three hours a day because fighting had damaged power lines. Most of the power lines from Israel that provided electricity for payment were previously damaged in the fighting.
This means most of Gaza will now be without power. The lack of electricity will also affect water supplies, since power is needed to operate water pumps.
Lt. Col. Peter Lerner, an Israeli military spokesman, did not comment on the explosion at the plant, but told The Associated Press that Israel's latest strikes signal "a gradual increase in the pressure" on Hamas.
Israel is "determined to strike this organization and relieve us of this threat," Lerner said.
International calls for an unconditional cease-fire have been mounting in recent days, as the extent of the destruction in Gaza became more apparent.
The house of the mayor of the Bureij in central Gaza was hit in an airstrike, and five bodies were pulled from the rubble, the Red Crescent said. Those killed included the mayor, 50-year-old Anas Abu Shamaleh, his 70-year-old father and three relatives.
In the southern town of Rafah, seven members of one family were killed in an airstrike and seven members of a second family were killed when tank shells hit their home, according to the Rafah office of the Palestinian Center for Human Rights, which keeps a casualty count.
In central Gaza, seven people, including five members of one family, where killed by tank shelling on a home, the Red Crescent said.
Tens of thousands of Gazans have been displaced by fighting in the border areas, which have come under heavy tank fire. Late Monday, Israel urged residents of three large neighborhoods in northeastern Gaza to leave their homes and immediate head to Gaza City.
In the West Bank, Yasser Abed Rabbo, the secretary general of the Palestine Liberation Organization, called for a 24-hour cease-fire and said the offer was made after consultations with Hamas and the smaller Islamic Jihad group.
However, Izzat Rishq, a senior Hamas official in exile, said his group wanted to hear from Israel first.
The largest group in the PLO is the Fatah movement of Palestinian President Mahmoud Abbas, Hamas' main political rival. Hamas is not a member.
Despite appeals for a cease-fire, both sides have been holding out for bigger gains.
Hamas has said it will not stop fighting until it wins international guarantees that a crippling border blockade of Gaza will be lifted. Israel and Egypt had imposed the closure after Hamas seized Gaza in 2007, defeating forces loyal to Abbas. Over the past year, Egypt has further tightened restrictions, shutting down hundreds of smuggling tunnels under the Egypt-Gaza border that had provide crucial tax income to Hamas. The closure of the tunnels drove Hamas into a severe financial crisis.
Israel has said it is defending its citizens against attack from Gaza by hitting Hamas rocket launchers, weapons storage sites and military tunnels under the Gaza-Israel border.
Israel said its troops will not leave Gaza until they have demolished the tunnels which have been used by Hamas to sneak into Israel to try to carry out attacks.
Enav reported from Jerusalem. Associated Press writer Ibrahim Barzak in Gaza City contributed to this report.