BEIRUT (AP) - U.S. officials say Israel was targeting a weapons convoy when it launched a rare airstrike inside Syria late Tuesday.

The convoy was believed to contain anti-aircraft weapons bound for Hezbollah militants in Lebanon.

Regional security officials say the strike targeted a site near the Lebanese border, while a Syrian army statement says it destroyed a military research center northwest of Damascus.

Regional officials say the weapons shipment included sophisticated Russian-made SA-17 aircraft missiles, which if acquired by Hezbollah would be "game-changing," enabling the militants to shoot down Israeli aircraft.

Syria's military denies the existence of any such shipment. They say two workers were killed at the research center and five others were wounded.

The Israeli military is declining comment.

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