Tel Aviv is closely watching the Hamas movement's activity in southern Lebanon, revealed Israeli security sources.
They added that Israel was preparing for various developments, including Hamas members there joining of any new confrontation that may erupt in the Gaza Strip.
Israel's Makan Arabic radio revealed that Hamas has intensified its activity in Lebanon after its relations with Turkey started to cool.
Hamas is hoping that its arm in Lebanon would act as a deterrence to Israel should a new battle between it and Israel erupt in Gaza.
Israeli security forces had been alerted to Hamas' activity in Lebanon in wake of a rocket attack in the Ras al-Ain region south of Lebanon's southern city of Tyre and an explosion that went off inside a mosque in the Bourj al-Shemali refugee camp.
The mosque was being used as a weapons depot.
Israeli authorities are trying to deal with the danger without causing an escalation. They are closely monitoring Hamas' military activity in southern Lebanon.
Security forces have not ruled out the possibility that Hamas, with the coordination of Hezbollah, would use its foothold in southern Lebanon to attack Israel should a new conflict erupt in Gaza.
The concerned agencies and military command are making the necessary arrangements to confront this threat, said Makan.
Israel had in April accused Hamas of firing a rocket from Lebanon.
It retaliated by shelling uninhabited areas and the location where the rocket was fired in southern Lebanon.
No one claimed responsibility for the firing of the grad rocket, but Israeli security circles said a Hamas cell was likely to blame.
