BEIRUT, Lebanon -- Hezbollah guerrillas shelled Israeli positions in a disputed border region for the first time in eight months Friday, drawing Israeli airstrikes and artillery fire and a sharp rebuke from the United States.
Hezbollah said its 2-hour attack was in retaliation for the killing of a Hezbollah security official Saturday south of Beirut. Hezbollah blamed Israel for killing Ali Hussein Saleh, who died when a bomb tore apart his car.
Hezbollah's Al-Manar television, quoting unnamed security sources, said the attack resulted in five Israeli casualties, but Israeli military sources said there were none.
In response to the attack, American diplomats told Lebanon and Syria -- which dominates Lebanon -- that the administration was seriously concerned about what a U.S. official described as a "calculated and provocative escalation" by the Shiite militant group. They told the two governments it was important to restrain further attacks.
The administration also told Syria and Lebanon the time has come for them to end their support for Hezbollah's terrorist operations, said the State Department's deputy spokesman, Philip T. Reeker.
Lebanese officials said Hezbollah forces fired a volley of rockets and mortar shells at the Israeli military outposts of Roueissat el-Alam, al-Samaka and al Radar inside the Israeli-occupied Chebaa Farms area. Witnesses reported seeing smoke rising from at least one position.
Israeli troops responded with an airstrike and 155mm artillery fire targeting suspected guerrilla hideouts in the outskirts of Kfar Chouba, a small farming village near Chebaa Farms, the officials said on condition of anonymity.
Two Israeli warplanes fired at least eight missiles into a valley and mountainous areas, the officials said.
Despite Israel's withdrawal from southern Lebanon, Israel remains locked in a territorial dispute with Hezbollah over the Chebaa Farms, which is claimed by Lebanon. Israel captured the area from Syria during the 1967 Mideast war. The United Nations says the region belongs to Syria, and that Syria and Israel should negotiate its fate.
An Israeli army spokesman said on condition of anonymity that there was "massive Hezbollah fire" on the Chebaa Farms, during which the militant group "fired anti-tank missiles, light weapons fire and mortars at several (Israeli army) posts."
Israeli forces returned artillery fire and Apache helicopters flew over the area searching for the source of the Hezbollah fire, the spokesman said, adding that two mortar shells fell in Masade in the Israeli-occupied Golan Heights.
The hostilities ended an eight-month lull on the Lebanese-Israeli border during the U.S. invasion of Iraq. Hezbollah, which is backed by Syria and Iran, had refrained from military action during that period to keep from giving Israel a pretext to attack Lebanon, the militant group's host.
In a statement faxed to The Associated Press, Hezbollah said it attacked the Israeli positions to avenge Saleh's death, "using rockets and other weapons and scoring direct hits."
Hezbollah anti-aircraft guns fired on Israeli warplanes over Lebanon. Israeli military sources said there was "no damage or injuries" from the fire.
Since Israel withdrew from southern Lebanon, Israeli warplanes have routinely flown over Lebanon on apparent reconnaissance missions, sometimes breaking the sound barrier with sonic booms and drawing fire from Lebanese troops and Hezbollah gunners.
Hezbollah led a guerrilla war against Israel's 18-year occupation of a southern Lebanon border zone, which ended in May 2000. Israel and the United States view Hezbollah as a terrorist group, but Lebanon regards it as a legitimate resistance movement opposed to Israeli occupation of Arab land.