GAZA CITY, Gaza Strip -- Israeli aircraft struck the Gaza Strip on Sunday, killing a Palestinian man, as militants bombarded the Jewish state with rockets and mortars in a fierce second day of fighting.
The clashes have threatened to draw the two sides into a major confrontation two months before Israeli elections, a possibility underlined by Prime Minister Benjamin Netanyahu's warning that Israel was ready to strike harder against the militants if the violence persisted.
"The world must understand that Israel will not sit idly in the face of attempts to attack us. We are prepared to intensify the response."
While cross-border fighting is a common occurrence, hostilities spiraled sharply over the weekend. An explosives-packed tunnel under the Gaza-Israel frontier blew up Thursday night in what the Israeli military called an attempt by Palestinian militants to kill or kidnap soldiers.
That set off a cycle of violence including Israeli airstrikes that have killed six Gazans and wounded almost 40, rocket and mortar barrages that have wounded four Israeli civilians, and the firing of an antitank missile into an Israeli military jeep patrolling the frontier area. The missile attack left four wounded, one critically - rare casualties for the Israeli side.
With the rocket fire disrupting life for tens of thousands of Israelis and soldiers being attacked with increasingly sophisticated weapons, the Israeli government is under stiff pressure from citizens to put an end to the violence.
Asked if a major operation against rocket squads was in the works, Israeli Defense Minister Ehud Barak said Israel was assessing the situation. He rejected the suggestion that Israel's upcoming Jan. 22 elections could affect the hardline government's response to the current round of violence.
"I don't think the elections have to have any effect on our response," he said. "It shouldn't cause us to refrain from acting, it's not handcuffing us. But it shouldn't provoke us to take an opportunity to launch an operation."
Gaza's rulers from the Islamic militant group Hamas, on the other hand, accused the Israeli government of escalating the violence in order to win votes in January elections.
"The Israeli government is responsible for all the consequences and implications of its escalation," said Hamas spokesman Fawzi Barhoum. "Hamas will not let Palestinian blood be a price for Israeli political and electoral gains."
In a precautionary measure, the group evacuated major security installations in fear of Israeli attack. But political leaders and government officials worked in their offices as usual.
In a development that could escalate hostilities, Hamas' military wing, the Izzedine al-Qassam Brigades, acknowledged taking part in the weekend rocket fire in a text message to reporters on Sunday.
While it remains virulently anti-Israel, Hamas has largely refrained from attacks since the Israeli military carried out a major offensive against Gaza rocket squads four years ago. It has also sought to keep things quiet as it consolidates control in the territory, which it seized five years ago in a violent takeover.
But it is under pressure from smaller militant groups in Gaza to prove it remains in confrontation with Israel and it sometimes joins the hostilities.
Although Israel considers Hamas responsible for all violence that comes from Gaza, Hamas' active participation in the fighting could make Israel respond more harshly to the attacks from the Palestinian territory.
