Lebanese authorities have arrested a Lebanese man accused of planning a suicide attack on behalf of Islamic State, state news agency NNA said on Tuesday.
The man told police that militants had trained him in north Lebanon and that an Islamic State operative in Iraq had taught him via the internet how to make an explosive belt, it said.
A security source said the plot was still at an early stage.
Another security source said authorities had arrested three people, including a Yemeni national, who formed "a terrorist cell linked to Islamic State".
Security forces found an explosive belt that they believed one of the suspects had intended to detonate in the southern suburbs of Beirut, the source added.
Interior Minister Nohad Machnouk praised the "success of the pre-emptive operation that prevented an explosion", NNA reported.
Islamic State, which has a large presence in neighboring Syria and holds a barren pocket of territory on its border with Lebanon, has attacked Lebanon in the past.
In November 2015 it was behind twin suicide bombings in south Beirut, an area mostly inhabited by Shi'ite Muslims, regarded by Islamic State as heretics.
Lebanese security sources also accused the group of carrying out eight suicide bombings in a Lebanese Christian village last summer that killed five people and wounded dozens more.
But Lebanon has mostly escaped the violence and chaos unleashed by Syria's war, where the Lebanese Shi'ite Hezbollah group has been fighting for President Bashar al-Assad.
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