The Lebanese military said seven soldiers were injured and a girl was killed as one of the assailants blew himself up in the midst of a family of refugees.
An explosive device also went off during a manhunt for suspected militants in one of the refugee camps, the army said, adding four others were defused.
The security source stressed that the raids were part of a major security sweep in an area that has been a flash point.
The army reportedly conducted the raids after intelligence reports said that militants were preparing to carry out a series of assaults inside Lebanon.
The Hezbollah resistance movement hailed the Friday operation, adding that the raids complemented its own fighters' campaign to ban the terrorists from entering Lebanon via Syria.
"What is needed today is to unify efforts more and more to fill all the gaps that terrorists can infiltrate from to protect Lebanon and its people from the big dangers that target it," the group said in a statement.
Lebanon is suffering from the spillover of militancy in neighboring Syria. Takfiri terrorists have been active on the Lebanese areas located close to the Syrian border.
Over the past few years, Hezbollah fighters have been offering a helping hand to the Syrian army in its fight against terrorists.
The resistance movement has also thwarted several terror attacks on the Lebanese side of the border.
Besides Daesh, Jabhat Fateh al-Sham, formerly known as Nusra Front, is also active around Arsal. Hezbollah and Lebanon’s army carry out joint operations against them on an almost daily basis.
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