by Sakher Abu El Oun Sakher Abu El Oun Wed Dec 24, 4:57 pm ET
GAZA CITY (AFP) – Hamas fighters fired off a barrage of rockets on Wednesday against Israel, which retaliated with a deadly air raid in an escalation of Gaza violence that is dimming prospects of a new truce.
Israel warned it would strike back if it continued to be hit from the impoverished Palestinian enclave, which has been under an increasingly tight Israeli blockade since the Islamists violently seized power in June 2007.
"Hamas is responsible for these rocket attacks, and it will pay a big price," said Defence Minister Ehud Barak on Israeli television Wednesday night.
"We will not allow this situation to last."
Hamas gunmen launched more than 70 projectiles, the largest barrage since before an Egyptian-brokered truce went into effect in and around Gaza in June but expired five days ago.
UN chief Ban Ki-moon expressed alarm about the violence and issued an urgent appeal for calm.
But Hamas -- which said Wednesday's rocket fire was in retaliation for the killing of three militants the day before -- vowed to step up attacks if Israel responded with strikes against Gaza.
"(Israel) should know that any decision to attack the Gaza Strip will open the gates of hell and we will make you regret your stupidity with tears of blood," the group's armed wing the Ezzedine Al-Qassam Brigades said.
"Israel's stupidity will push us to expand (operations) and put in our line of fire thousands of new Zionists to defend the Palestinian people."
Israel in turn warned it would hit back, although analysts said it was likely to be wary of major action ahead of a February election.
President Shimon Peres, on a visit to the town of Sderot which has borne the brunt of rocket attacks, said Israel's response must be "measured, responsible and efficient."
Israel's security cabinet met for five hours to discuss possible action, but Prime Minister Ehud Olmert imposed a black-out.
Late on Wednesday, Hamas fighter Yahi al-Shaaher, 23, was killed and four other Palestinians wounded when an Israeli helicopter fired three missiles near the southern town of Rafah, medics and witnesses said.
An Israeli army spokesman said the raid targeted rocket-firing "terrorists."
Wednesday's rocket barrage did not cause injuries but sowed panic among Israelis living near Gaza. An alert system has been set up to warn towns and villages near the border of any imminent strike.
Two of the rockets were longer-range Grads, which struck 13 kilometres (eight miles) north of Gaza, hitting a house and an amusement park in the city of Ashkelon, Israeli and Palestinian officials said.
Grads are not fired often by Gaza militants, who usually launch home-made projectiles dubbed Qassams, which have a shorter range and are less accurate.
A UN statement said Ban was "gravely concerned" about the situation and that he condemned the rocket attacks, while also calling for an urgent easing of humanitarian conditions in the Gaza Strip.
Since Friday's expiry of the Egyptian-mediated truce, Israel has threatened to launch a major offensive on Gaza and Hamas warned it would retaliate by resuming suicide attacks inside the Jewish state.
Israel, which considers Hamas a terrorist group as it is sworn to the destruction of the Jewish state, kept Gaza sealed on Wednesday.
Aid groups have warned of a deteriorating humanitarian situation in the tiny enclave, virtually cut off from the outside world since Hamas violently ousted its rivals from Palestinian president Mahmud Abbas's Fatah faction.
They have repeatedly appealed to Israel to ease its blockade and allow shipments into Gaza, where most of the 1.5 million population depends on foreign aid.
Mahmud Zahar, a hardline Hamas leader, said on Tuesday that the group was ready to renew the truce if Israel lifted its blockade and stopped raids.
Israeli Foreign Minister Tzipi Livni was due to travel to Cairo on Thursday for talks with Egyptian President Hosni Mubarak on the ceasefire.
Both Israel and Hamas face delicate balancing acts in dealing with the escalation.
Ahead of the election, the Israeli leadership is maintaining a tough line in public, but is wary of launching a large-scale offensive for fear it does not score a decisive victory against Hamas, analysts say.
And Hamas, despite its bellicose public statements, does not want an all-out Israeli assault that could threaten its position, they say.
