"Zionist planes attacked the outskirts of the village of Tair Harfa in south Lebanon," Hizb Allah's al-Manar television said in a news flash.
Earlier on Sunday an anti-aircraft shell fired by Lebanese guerrilla group Hizb Allah at Israeli warplanes, killed one person in Israel, military sources said.
Witnesses told Reuters that Israeli planes and helicopters had been flying over south Lebanon all morning and continued their overflights into Lebanese territory after the airstrikes.
Border conflict reignited
The death was the first in northern Israel by Hizb Allah fire since Israel was forced to withdraw from south Lebanon in 2000 after a 22-year occupation.
Earlier on Sunday, one Israeli was killed and five wounded in what Israel said was the second border attack in three days by Lebanon-based Hizb Allah militia after a seven-month lull, fuelling fears in the Jewish state of the reopening of a northern front.
"This is a clear provocation by Hizb Allah and Israel will not sit idly by"
Israeli government spokesman
The Shia resistance group said it only fired anti-aircraft guns at Israeli planes overflying Lebanon, but Israeli military sources said Hizb Allah had fired shells across the border in a deliberate attack, and warned it would not sit idly by.
Pressure on northern neighbours
The incident came as Israel was already stepping up pressure on Syria and Lebanon to end their support for Hizb Allah, and was considering seeking a special meeting of the UN Security Council on the situation.
Two Israelis were wounded by falling anti-aircraft fire in July, but military sources stressed that Hizb Allah had fired 57mm artillery rounds on Sunday in a deliberate attack on Israeli territory.
"This is a clear provocation by Hizb Allah and Israel will not sit idly by," Israeli government spokesman Avi Pazner told AFP.
"We consider Hizb Allah and those who support it as entirely responsible for the situation," he added, in a reference to Syria and Iran.
Israeli Foreign Minister, Silvan Shalom, had warned before the Sunday attack that any casualties in one of Hizb Allah's border attacks would trigger a tough response.
"If our citizens are hit we will have to defend them, and Syria and Lebanon would be well advised not to put us to the challenge," he told public radio.
The first deadly border incident in almost a year came against the tense backdrop created by Hizb Allah's first rocket attack in seven months, on Friday.
The group, which controls southern Lebanon, fired rockets and mortar bombs on the disputed border area of the Shebaa Farms on Friday, causing no casualties but prompting a swift military response by Israel.
Israel also upped the diplomatic ante following Friday's attack, lodging a complaint on Saturday with the UN against Syria's support for Hizb Allah.
Kofi Annan expressed concern
Because Damascus holds the rotating chairmanship of the Security Council, Syrian ambassador Mikhail Wehbe is not allowed to answer the protest.
The United Nations has not been Israel's favourite turf to challenge its enemies, but following UN Secretary General Kofi Annan's unequivocal condemnation of Friday's attack, the foreign ministry was mulling demanding an emergency meeting of the Security Council should be convened.
"We are considering filing a request for an emergency meeting of the Security Council," said David Granit, an Israeli foreign ministry official in charge of relations with the UN.
"For the first time, Annan has mentioned a provocation against Israel emanating from an Arab country, and we are assessing the impact of this new stance on UN member countries," Granit told AFP.
The official was referring to a statement on Friday in which Annan said he was "very concerned at the exchanges of fire across the Blue Line in Southern Lebanon, initiated from Lebanese territory."