Lebanese security officials say a Syrian government helicopter has fired three missiles on a border town in northern Lebanon.

The officials say one of the missiles struck the center of Arsal on Wednesday. It's the first such attack from Syria on an urban center inside Lebanon. There was no immediate word on casualties.

Scores of rebels and civilians who fled from the Syrian western town of Qusair last week in the last days of a government military offensive have taken refuge in Arsal.

Support for the rebels fighting to topple Assad runs high in the predominantly Sunni Muslim town.

The Lebanese officials spoke on condition of anonymity in line with military regulations.