ISRAEL accused Lebanon of an act of war yesterday after Hezbollah guerrillas captured two Israeli soldiers in a daring cross-border raid and killed eight others.

Within hours Israeli warplanes, tanks and gunboats were shelling southern Lebanon, and Ehud Olmert, the Israeli Prime Minister, promised “very, very, very painful” reprisals.

The events marked a dramatic escalation in the stand-off over the Israeli soldier held hostage in the Gaza Strip, and threatened to turn a localised incident into a regional conflagration. Mr Olmert, facing his most serious test since he took over from Ariel Sharon, said: “The murderous attack that took place this morning was not a terror attack. It was an act of war by the state of Lebanon against the state of Israel within its sovereign territory .”

As he spoke, F16 jets destroyed three bridges crossing the Litani river, cutting off much of southeast Lebanon from the capital, Beirut. Israeli troops also crossed into Lebanon for the first time since they withdrew in 2000 after an 18-year occupation.

The Israeli military, already stretched by operations in Gaza, where it bombed the Palestinian foreign ministry early today, called up thousands of reservists. An emergency Cabinet meeting last night authorised a “severe response” against Hezbollah.

Sheikh Hassan Nasrallah, Hezbollah’s leader, said that the raid was carried out in solidarity with Palestin-ians under siege in Gaza, and the Israeli soldiers would only be released if Israel freed Lebanese prisoners.

“No military operation will return them. The prisoners will not be returned except through one way: indirect negotiations and a trade,” he said.

The action began at 2.30am when Israeli warplanes bombed a house in Gaza in an effort to kill Mohammed Deif, leader of Hamas’s military wing. Deif was severely injured, and another Hamas activist and his wife and seven children were killed.

Hours later Hezbollah fighters crossed the Lebanese border into Israel, killing three Israeli soldiers and taking two hostage. Israeli troops pursued the raiders back across the border, where an Israeli tank was blown up, killing five more soldiers. Lieutenant-General Dan Halutz, the army chief of staff, said that Israel would “turn back the clock in Lebanon by 20 years” if the soldiers were not freed.

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