Israel pounds Gaza for second day after killing 280 Palestinians

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GAZA, Dec 28 (Reuters): Israel destroyed Hamas's main Gaza security complex in an air strike Sunday and prepared for a possible invasion of the territory after killing more than 280 Palestinians in the first 24 hours of a powerful offensive.
Israeli leaders said the campaign was a response to almost daily cross-border rocket and mortar fire that intensified after Hamas, an Islamist group in charge of the coastal enclave Israel quit in 2005, ended a six-month ceasefire a week ago.
Despite the air assaults, militants fired some 80 rockets into Israel, emergency services said. In one of the deepest attacks, two rockets struck near Ashdod, a main port some 30 km (18 miles) from Gaza, causing no casualties, police said.
Israeli tanks deployed on the edge of the Gaza Strip, poised to enter the impoverished enclave where 1.5 million Palestinians live. Prime Minister Ehud Olmert's cabinet approved a limited call-up of reservists, officials said.
"Israel will continue (the campaign) until we have a new security environment in the south, when the population there will not longer live in terror and in fear of constant rocket barrages," said Mark Regev, a spokesman for Olmert.
The U.N. Security Council called for a halt to the violence.
Keeping pressure on Hamas after one of the bloodiest days for Palestinians in 60 years of conflict, Israeli aircraft flattened the group's main security compound in Gaza, killing at least four security men, a health official said.
The deaths raised to 286 the number of Palestinians killed since Saturday, when Israel launched what one Israeli newspaper columnist described as "shock and awe" air strikes against Hamas facilities. More than 700 Palestinians were wounded
"Palestine has never seen an uglier massacre," said Hamas leader Ismail Haniyeh. His Islamist group vowed revenge including suicide bombings in Israel's "cafes and streets."
One Israeli was killed Saturday by a rocket fired from the Gaza Strip.
Israeli military affairs commentators said the Israeli offensive did not appear to be aimed at retaking the Gaza Strip or destroying the territory's Hamas government -- ambitious goals that could prove difficult and politically risky to achieve ahead of Israel's February 10 parliamentary election.
Instead, they said, Israel -- after an air bombardment on Saturday -- wanted to strengthen its deterrence power and force Hamas into a new truce that would lead to a long-term halt to cross-border rocket salvoes.
In the Gaza Strip, where normally bustling streets were largely traffic-free, Palestinians stood outside their homes to chat with neighbors about the dangers ahead as the roar of Israeli aircraft and explosions echoed in the distance.
Israeli Defense Minister Ehud Barak ordered schools, due to reopen on Tuesday after the Jewish holiday of Hannukah, to remain shut in southern Israeli communities.
Along the Gaza border, a Reuters photographer saw Israeli soldiers cleaning the barrels of their tanks taking cover under the armored vehicles as Palestinian rockets flew overhead.
Meanwhile: Israel has warned it could send ground troops into Gaza as its warplanes continued pounding Hamas targets inside the enclave where more than 270 Palestinians have been killed in just 24 hours.