The State Department's spokesperson condemned Syrian airstrikes targeting rebel fighting in Lebanon Monday.
The airstrikes "constitutes a significant escalation in the violations of Lebanese sovereignty that the Syrian regime has been guilty of," Victoria Nuland said. "These kinds of violations of sovereignty are absolutely unacceptable."
Reports indicate that regime Syrian forces fired four rockets Monday morning near the Bekaa Valley town of Arsal, whose community is known to support the anti-Assad forces.
Lebanon has maintained a policy of "disassociation" from Syria's ongoing civil war. However, acts like this violation of sovereignty and border crossings by Syrian rebels are making it increasingly difficult for Lebanese officials to remain on the sidelines.
The airstrikes come on the same day that president Assad's wife made her first public appearance in months.