Lebanon's police say they have detained a Syrian citizen who was a military commander with the Islamic State group in the central Syrian province of Homs.

The Internal Security Forces said in a statement on Tuesday that the man was detained earlier this month in the northern town of Zgharta after entering Lebanon illegally from Syria.

It identified him as a Syrian citizen born in 1982 without giving his name.

The statement said the ISIS fighter confessed to being "a military cadre" who took part in many battles in Syria including the capture of the historic town of Palmyra that the extremists held for months and destroyed some of its invaluable archaeological sites.

ISIS carried out many deadly attacks in Lebanon in recent years that left scores dead.