The fighter bombers provoked two loud booms at around 10:55 amover the southern region of Marjayoun before flying to break the sound barrier over the nearby port city of Tyre, they said.

The jets then flew on, causing more booms over the Shebaa Farms, a border area where the Lebanese Shiite Muslim group Hezbollah is leading a guerrilla war against Israeli forces occupying the territory.

The warplanes then broke the sound barrier over the eastern city of Baalbek, a main Hezbollah stronghold, before zooming up north to do the same beyond the port city of Tripoli, close to the Syrian border.

Hezbollah -- backed by Lebanon, Syria and Iran -- has threatened Israel with "costly" reprisals if its air force continues its almost daily violations of Lebanese airspace despite UN condemnation.

Overnight Sunday, Israeli jets staged mock air raids over Beirut in retaliation for Hezbollah fire that killed one person and wounded five others in northern Israel earlier in the day.

Hezbollah said it only fired anti-aircraft guns at Israeli warplanes overflying Lebanon, but Israel countered by saying Hezbollah had fired across the border in a deliberate attack, swiftly mounting a retaliatory strike.

That prompted Lebanon to open a diplomatic campaign to prevent Israel from carrying out threats of retaliatory air strikes.

WAR.WIRE