More than a dozen members of the Lebanese military died in a raid on Assir's compound in the coastal city of Sidon last weekend. He is viewed as a militant cleric who has spoken out against Hezbollah's role in the fight against Syrian rebels battling forces loyal to Syrian President Bashar Assad.
Judicial authorities told Lebanese newspaper The Daily Star on condition of anonymity some of the soldiers involved in the raid were arrested for abusing a detainee.
A video cross-posted on The Daily Star's website shows men wearing Lebanese military patches beating a detainee during what appears to be an impromptu interrogation of an Assir loyalist.
The Lebanese government this week praised the military's operations in Sidon, saying the death of the soldiers should not be in vain.
Lebanese national security is in jeopardy because of the threat of spillover from Syria's civil war. The Syrian government held significant influence over political affairs before Lebanon's Cedar Revolution in 2005 ensured the country's national sovereignty.