The trucks were stopped in Saad Nae'l town in Bekaa, Syria's official SANA news agency reported.
"The Captagon tablets were hidden inside the chassis of the 6 trucks. ... We stopped a car that was accompanying those trucks with three Syrians inside," a security official said.
Captagon contains fenethylline, a stimulant that is most common in Arab countries.
The three Syrians, identified as Abdel Rahman Khaled Srour, 21, Sabei Adnan Srour, 27 and Yehya Mahmoud al-Mkahhal, 51, were arrested at the scene, The (Beirut) Daily Star reported.
In March, security authorities seized more than 1 million Captagon pills in a valley in the Bekaa region, Naharnet reported. Officials said that seizure was worth millions of U.S. dollars.
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