Lebanon's army has detained about 450 suspected Islamist militants near its border with Syria, Lebanese security sources said on Thursday, as it steps up efforts to prevent them from using the frontier town of Arsal as a base, Al Arabiya reported.
Arsal was the scene of last month of the deadliest spillover of fighting in the three-year civil war in Syria.
During those clashes that killed dozens, militants captured a group of Lebanese soldiers and have since killed at least three of them. They are believed to be holding more than a dozen others.
In the last two weeks, the army has arrested hundreds of mostly Syrian suspects there that it accuses of being members of extremist groups such as Nusra Front, Syria's al Qaeda wing, which is fighting Syrian President Bashar al-Assad's forces.
The army said on Thursday it had searched a camp near the border for suspects. It gave no further details.
Anti-Assad insurgents often cross the porous border, using Arsal to rest or seek medical treatment, and the town also hosts tens of thousands of Syrian refugees.
Sunni Muslim militants and other groups in Syria accuse the Lebanese army of working with Hezbollah, the Lebanese Shiite movement which has sent fighters to help Assad's forces.