A military source told AFP that the man had managed to network with Lebanese security and intelligence officials, telling them he worked at Iraq's Beirut embassy.

The scandals have highlighted the fragility of Lebanon's institutions, which are built on a sect-based power-sharing system in a country rife with foreign interference, and where personal connections often play a key role in gaining influence, money and privilege.

An army statement said the Iraqi man was arrested "for impersonating an Iraqi security official on Lebanese territory, as a result of a surveillance and security follow-up operation".

Preliminary investigations indicate that the man was using "forged documents", the statement said, adding that the military uniform he had been using was seized.

The military source told AFP on condition of anonymity that the man "is married to a Lebanese woman and managed to get close to an intelligence official in Beirut, presenting himself as an Iraqi officer in the counter-terrorism branch, and a security attache at the Iraqi embassy".

The Lebanese intelligence official allegedly helped the man "make contact with security and military officials and meet them", the source said.

The suspect actually works at a popular cafe on the airport road in Beirut's southern suburbs, the source added, after he started out there doing valet parking.

It is the second recent high-level impersonation case to rock Lebanon.

For months, authorities have been investigating an imposter who posed as a Saudi prince, extorting several politicians with the help of a religious figure.

A former prime minister and several other politicians, most of them Sunni Muslim, were caught up in the scandal that exposed the country's deep-rooted corruption.

The military source said that in the latest case, preliminary investigations into the man and those who met him have not yet uncovered a motive, adding that during the meetings "he promised to provide financial assistance from Iraq".

The case's seriousness owes to the man's ability to "convince intelligence officers of his fake identity", the source added.