The official said Tuesday that Mohammad Ali al-Husseini was detained Saturday. He says the cleric will be referred to military court if the charges are confirmed. He spoke on condition of anonymity in line with regulations.
Lebanon and Israel technically remain at war, and more than 100 people have been arrested in Lebanon since 2009 on suspicion of spying.
The detention marks a rare instance of a clergyman's suspected involvement in a spying case. Al-Husseini is known to be against Hezbollah, the Shiite militant group that fought a war with Israel in 2006.