BEIRUT, Lebanon — Israeli warplanes launched two raids near the Syrian-Lebanese border late Monday, according to Lebanon’s National News Agency, raising speculation that Israel might have targeted a weapons convoy to prevent the Syrian government from delivering missiles to its Lebanese ally, Hezbollah.

Israel has struck Syria at least three times in the past year, according to United States officials, to prevent sophisticated weapons from reaching Hezbollah amid the chaos of Syria’s war. Neither Syria nor Hezbollah has retaliated.

The potential significance of Monday’s strike depended on whether the raids hit Syrian or Lebanese territory, which was not immediately clear. Analysts said it would be politically harder for Hezbollah to refrain from striking back if Israel, its longtime enemy, had struck inside Lebanon.

An Israeli strike inside Lebanon would also represent a further escalation in the regional involvement in — and spillover from — the Syrian conflict. Israel and Hezbollah fought a war in the summer of 2006.