A Lebanese arrested on suspicion of spying for Israel has confessed to have helped in the assassination of a Hezbollah commander in 2004, a senior security source said on Tuesday.
The source said Michel Abdo was arrested three weeks ago and is considered "a very important spy". He will be tried before a military court.
"His role was to facilitate the movement of the Israeli Mossad agents who carried out the assassination," the source told Reuters.
"He picked them up from a point near the sea south of Beirut and took them to his house where they planed the assassination he then facilitated their departure," the source said.
Israel, which fought a 34-day war with Hezbollah in 2006 has not commented on the arrests.
Ghalib Awali, a Hezbollah military commander, was killed by a bomb in the southern suburbs of Beirut in 2004 as he got into his car. Abdo is the second suspect to be tied to his killing.
Israel assassinated the group's leader Abbas al-Mussawi in 1992 in an air strike on his car. Lebanon has tried and convicted several people in recent years of spying on and plotting against the group.
A probe into spying for Israel has led to more than 50 arrests since April. More than 20 have been formally charged.
Lebanon, which is in a state of war with Israel, has described the arrests as a blow to Israel's intelligence-gathering in the country. Hezbollah has called for the death penalty for all suspects convicted.
Lebanese courts have handed down what were widely seen as light sentences against Lebanese who have worked with the Israeli occupation and its local militias after Israeli forces ended a 22-year occupation of mainly Shi'ite south Lebanon in May 2000.
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