A car bomb exploded Saturday in southern Turkey near the border with Syria, killing at least 50 people. The Turkish government blamed the attack on pro-government forces in Syria.
Lebanese President Michel Suleiman said Monday he was concerned about the spread of violence.
"Those behind the attack, whatever their affiliation, must be punished," he was quoted by The Daily Star newspaper in Lebanon as saying.
Fears of spillover have spread as Syrian civil war is into its third year. Lebanon has been on edge amid accusations that forces form Shiite resistance movement Hezbollah may be supporting pro-government forces in Syria.
Turkish Prime Minister Recep Tayyip Erdogan said last weekend that those behind the attack would pay. The Turkish military, however, wouldn't get pushed to war, he added.
NATO sent the Patriot missile defense system to the Turkish border last year to protect its ally from war. There are no plans for a no-fly zone over Syria, however.