Two hundred Israeli soldiers, supported by two tanks, seized the barracks in the mainly Christian town of Marjayoun but a senior Lebanese officer told Aljazeera that there were now signs that they were planning to leave.
Ahmad Fatfat, the acting Lebanese interior minister, said: "It appears from the ongoing contacts, which included the US secretary of state [Condoleezza Rice] and senior French officials ... there is a big hope they will leave the barracks without harming any of the security personnel."
Earlier on Thursday, Israeli troops had searched the armoury at the barracks for rockets and other heavy weapons but left after finding none.
Humanitarian mission
Referring to the Lebanese troops at the barracks, Fatfat said: "They are armed only with individual weapons because they did not have a combat mission, but essentially a humanitarian [mission] to help residents of these areas.
"Our impression is that they might have wanted to use the Marjayoun barracks as a kind of human shield."
Israeli troops had come under heavy fire from Hezbollah rockets and mortars before entering the barracks.
They took control of the whole town for about six hours before advancing on the nearby town of Khiam.
Israeli units were holding positions around the western and southern suburbs of Khiam which has been severely damaged by previous air raids.