BAALBEK, Lebanon - Lebanon's army used its anti-aircraft defence systems to fire at Syrian helicopters after they carried out a raid in Lebanese territory on Monday, a military source told AFP.
It was the first time the Lebanese army has responded to Syrian attacks inside Lebanese territory, which have multiplied as the conflict in Syria spills over the border.
"In accordance with the orders of the army command, anti-aircraft guns were fired in the direction of Syrian helicopters that bombed Khirbet Dawud near Arsal," in the area near the Syrian border, the source told AFP.
"It is the first time that the Lebanese army has used its anti-aircraft defence systems" to respond to Syrian raids, the source added.
There were no injuries in the Syrian raid and it was not clear whether the Lebanese fire had hit the Syrian aircraft.
Lebanon's army has in the past threatened to respond to fire into the country from across the border in Syria and Syrian raids inside Lebanese territory.
On June 12 it issued a rare warning to Syria, saying it would respond "immediately" to any new "violation" after a Syrian raid on the Arsal area.
Syrian warplanes and helicopters have regularly carried out raids in the border area inside Lebanon, particularly around Arsal - a Sunni region where many support the Syrian uprising.
Arsal is also home to tens of thousands of Syrian refugees who have fled the conflict that began in March 2011 and has killed more than 126,000 people.