Lebanese security officials say 16 rockets fired from Syria have struck the eastern region of Baalbek.
The officials, who spoke on condition of anonymity because they were not authorized to brief reporters, say the rockets caused a fire in fields without casualties.
The area that was struck is a stronghold of Lebanon's militant Hezbollah group that is fighting alongside Syrian President Bashar Assad's forces against rebels who are trying to remove him from power.
Rebels have fired dozens of rockets on Lebanon's northeastern region of Hermel over the past weeks but Saturday's attack was the first on Baalbek.
Syria's two-year civil war has spilled over to Lebanon where fighters who back and oppose Assad have clashed, leaving scores dead and wounded in recent months.
Want to enjoy 'Zen' reading - with no ads and just the article? Subscribe todaySubscribe now