Our colleague Barry Rubin reports:

It has been reported–but not confirmed–that Israel’s air force hit a convoy near the Syrian-Lebanese border, presumably chemical weapons being shipped to Hizballah. This is NOT yet confirmed by Israel.

The Independent has more details.

If this pans out, it is a major development. Syria’s possession of chemical weapons has been long known, as has its alliance with Hizballah.

The Obama administration last year warned the Syrian regime against using chemical weapons in its ongoing civil war.

Update: The Jerusalem Post reports:

An unnamed security source told AFP: “The Israeli air force blew up a convoy which had just crossed the border from Syria into Lebanon.”

An activist in Syria who works with a network of opposition groups around the country said that she had heard of a strike in southern Syria from her colleagues but could not confirm.

The IDF has declined to comment on reports of a strike on the Syrian-Lebanese border. “We do not comment on reports of this kind,” an IDF spokeswoman said.

Update: YNet News reports:

The two officials did not say what the target was. But they said Wednesday that Israel had been making plans in the days leading up to the airstrike to hit a shipment of weapons bound for the anti-Israel militant group Hezbollah in Lebanon.

They said the shipment included sophisticated, Russian-made SA-17 anti-aircraft missiles, which would be strategically “game-changing” in the hands of Hezbollah.

SA-17 missiles are self-propelled and have the capacity to hit jets at a low altitude. Its downside is its radar dependency.

Analysts estimate that Assad’s regime has a clear interest in transferring advanced “game-changing” weapons to Hezbollah in order to repay it for its assistance in Syria’s war against the rebels and to prevent the weapons from falling into rebels’ hands.

Hezbollah in turn could use the long-range Scud-D missiles to threaten Israel’s hinterland and defend itself against an Israeli airstrike.