Israeli security forces attacked a target on the Syrian-Lebanese border overnight, sources told Reuters on Wednesday.
The report cited two unnamed officials, a western diplomat and a "security source," who confirmed that the attack took place but were unable to provide additional information. In recent days, Israel had expressed concern over the stability of Syria's arsenal of chemical and conventional weapons. The Israeli military declined to comment, according to Reuters.
The sources, who declined to be named because of the sensitivity of the issue, had no further information about what might have been hit or where precisely the attack happened.
Earlier, the Lebanese army reported a heavy presence of Israeli jets over its territory throughout the night.
"There was definitely a hit in the border area," the source said.
Israel's vice premier Silvan Shalom said on Sunday that any sign that Syria's grip on its chemical weapons was slipping, as President Bashar al-Assad fights rebels trying to overthrow him, could trigger Israeli intervention.