Hezbollah on Saturday denied having fired a rocket from Lebanon that hit northern Israel earlier in the day, lightly wounding two people.
Ibrahim Mussawi, a spokesman for the militant organization, told AFP that Hezbollah had "nothing to do" with the attack, which was launched from a region largely controlled by Hezbollah and its Amal party ally.
Three other people were treated for shock after the attack, and a house was damaged, the Israel Defense Forces said.
During the IDF's punishing offensive against Hamas in Gaza last month, three Katyusha rockets were fired into northern Israel within a week, hitting Nahariya and Kiryat Shmona.
Hezbollah, which has a large rocket arsenal, was behind the two rocket attacks. In both cases, the organization used proxy Palestinian militant groups to launch the rockets from southern Lebanon.
Meanwhile, a Lebanese security source in Beirut said Israel had responded by firing at least six artillery shells into southern Lebanon.
The IDF Spokesperson's Office later said Israel held the Lebanese government and the Lebanese army accountable.
The rocket exploded a few meters from a house, where a 20-year-old was lightly wounded in her sleep.
"Shattered glass was scattered all over the house," her father said. "Not a single window pane remained intact."
The leader of the local council said that the incident came "out of the blue."
Because of the stormy weather, he said, some people thought that the explosion was a thunder.
The Lebanese source, asking not to be identified, said: "Two rockets were fired from the area of Mansouri, south of Tyre, towards the direction of Israel."
"One of these rockets landed [within Lebanese territory]. The other rocket's location has not been determined," said the source.
No one claimed responsibility for the rocket firing.
A statement from Lebanese Prime Minister Fouad Siniora's office said Lebanon was committed to implementing UN Security Council resolution 1701 which ended a month-long war between Israel and Hezbollah guerrillas in 2006.
He said the attack threatened the area's stability and condemned Israel's artillery fire.
"Prime Minister Siniora [said] the rockets launched from the south threaten security and stability in this region and are a violation of resolution 1701, and these issues are rejected, condemned and denounced... Israeli artillery [fire is an] inexcusable violation of Lebanese sovereignty," the statement said.
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