A Palestinian rocket struck an Israeli army base early Tuesday, wounding dozens of soldiers and prompting calls for a major military operation in the Gaza Strip.

The rocket struck as the soldiers, all recent recruits undergoing training, slept in their tents at the army's Zikim base north of the Gaza-Israel border.

It directly hit an empty tent just before 2 a.m., said the army. More than 40 soldiers in nearby tents were injured, 12 remain in serious condition.

Ambulances and army helicopters evacuated the seriously wounded to hospital.

The injury toll marks the highest ever sustained by a single Palestinian rocket attack.

The army launched an initial response Tuesday, sending ground forces to the area where Israeli officials believed the rocket came from.

Gaza's Health Ministry said four Palestinian civilians from the same family, between the ages of 5 and 21, were wounded.

Israeli Prime Minister Ehud Olmert is set to meet later Tuesday with top military and security officials to discuss a possible response.

The attack comes as many Israeli officials call for a more aggressive stance to be taken against the constant rocket barrages out of Gaza.

"Long ago, several years ago, we should have responded strongly ... In the end we will have no choice but to act,'' cabinet minister Eli Yishai told Army Radio.

CTV's Janis Mackey Frayer reported Tuesday that Olmert is most likely to hold off on a large-scale incursion until after the holiday season -- which starts this week with the Jewish New Year.

Frayer said there are also concerns that if an operation was launched it would leave Israel vulnerable in the north -- at a time when tensions remain high with Syria.

In a joint statement faxed to reporters, two small extremist groups -- Islamic Jihad and the Popular Resistance Committees -- claimed responsibility for the attack.

While Islamic Jihad has been behind most of the rocket fire out of Gaza recently, Israel still holds Hamas responsible since it controls the region.

Hamas spokesman Fawzi Barhoum praised Tuesday's attack as a "victory from God.''

Israel officials rejected calls last week for a large-scale Gaza invasion. However, they have threatened to suspend water, electricity and fuel supplies to Gaza.

In 2005, Israel pulled out of Gaza after 38 years of military rule. Despite the move, militants continue launching rockets across the border into Israel.

With files from The Associated Press