Israeli warplanes frequently fly over Lebanese airspace in what Israel says are reconnaissance missions, but this was the first time the Lebanese army has fired on the aircraft since an Aug. 14, 2006, cease-fire ended a month-long war between Israel and Hezbollah guerrillas in Lebanon.
Lebanese soldiers opened up with machine guns and light anti-aircraft weapons mounted on armored vehicles at two planes that flew by just east of Marjayoun, a town near the border, at midmorning, a Lebanese security official said.
A total of 150 rounds were fired, he added.
A senior military officer also said the army "confronted" the Israeli planes, but gave no details.
Both officials spoke on condition of anonymity in the absence of a formal announcement from the military command.
The Israeli military does not comment on air operations, but there were no reports from Jerusalem of any planes being hit.
CBS News correspondent Robert Berger reports Israeli jets often fly over Lebanon to monitor alleged weapons smuggling from Syria to Hezbollah guerrillas.
Earlier this year, Lebanese and Israeli soldiers briefly exchanged fire near the border village of Maroun el-Rass where the U.N.-demarcated Blue Line was not clearly marked. There were no casualties.
Israeli overflights have been a constant source of tension between the two countries. Before last year's war, Hezbollah used to open fire on Israeli planes, with shrapnel from the anti-aircraft fire falling on Israeli communities across the border, causing some casualties.
The deployment of about 15,000 Lebanese troops in the south along with some 13,000 U.N. peacekeepers after the U.N.-brokered cease-fire has not stopped the flyovers despite the U.N. describing them as a violation of Lebanese sovereignty.
Lebanese Political Crisis
Both Hezbollah and Israel claimed victory after the fighting stopped in 2006. Practically, the militant Islamic group did gain some clout for having put up such a fight against one of the most potent militaries in the region.
Hezbollah supporters form a formidable political opposition to Lebanon's moderate, Western-backed prime minister, Fuad Saniora - who's government is teetering on the verge of collapse.
The attempt to choose a successor to pro-Syrian President Emile Lahoud before he steps down on Nov. 24 has become Lebanon's most serious political crisis since the end of the 1975-90 civil war.
Syria denies it is interfering in Lebanese affairs. Its allies in Lebanon, led by Hezbollah, accuse the United States of interfering by discouraging agreement on a compromise candidate.
Visiting Beirut on Thursday, Egypt's foreign minister called for an end to foreign interference in Lebanon and urged feuding politicians to elect a president on time.
Foreign Minister Ahmed Aboul Gheit said he was carrying no specific initiative to help Lebanese leaders overcome their differences, but would offer ideas.
"We seek to help by conveying to the leaders an Egyptian vision that encourages constructive dialogue... that would secure a successful election," he told reporters in Beirut.
"We do not interfere in who gets elected. This is an internal affair and we hope all foreign interference in Lebanon would stop," he said, in an apparent reference to Syria.
His visit comes few hours after U.N. Secretary-General Ban Ki-moon warned against a power vacuum that could splinter the government in Lebanon and also called for an end to "foreign interference."
In a report to the Security Council Wednesday, Ban made clear that he was particularly referring to Syria. The United States and European leaders have also called for Syria to cease its interference in the affairs of its smaller neighbor.