Israel has declined to comment on reports that its army launched an attack in the Syrian border area on Wednesday night.
Lebanese security sources claim Israeli forces hit an armed convoy on the Syria-Lebanon border.
The reports come at a time of growing concern about Syria’s arsenal of chemical weaponry, as the civil war there continues to escalate.
The Lebanese army says there was a strong presence of Israeli jets overnight.
There is no confirmed information about the exact nature or location of the target.
Israeli Prime Minister Benjamin Netanyahu held a meeting of security chiefs to discuss Syria last week.
And his vice premier Silvan Shalom said on Sunday that any sign that the country is losing its grip on its chemical weapons could trigger Israeli military strikes.