Lebanese security forces have raided a hotel and arrested at least 17 suspected Isis militants on suspicion of plotting to kill a leading Shiite politician.

The militants from the Islamic State of Iraq and the Levant were held for planning to assassinate Nabih Berri, the parliamentary speaker and leader of the Shiite Amal political party, and Maj. Gen. Abbas Ibrahim, head of Lebanon's General Security Directorate, local news website NOW Lebanon reported.

Approximately 200 armed officers from Lebanon's Internal Security Forces swooped on the Napoleon Hotel, blocking off streets in West Beirut's main commercial district.

The officers forced civilians off the street before leading 12 suspected militants, with their heads covered, into cars. Five other suspects were arrested in the surrounding area.

A source, speaking of condition of anonymity, told Lebanon's Daily Star that the State Prosecutor Samir Hammoud ordered the raid following a tip-off about "the presence of terrorists" who were "preparing a big terrorist operation" in the Hamra area.

Local television channels said that security forces were still searching for suspects in the Hamra district and that those arrested were mostly of foreign nationalities, including Pakistanis, Iraqis and Syrians.

The Amal party, allies of the Lebanese Shiite party and militant group Hezbollah, had earlier cancelled a Beirut conference because of security concerns.

Before the raid, Ibrahim had escaped a suicide car bombing in Lebanon's Bekaa Valley which killed a member of the security forces and wounded another 32 people.

Isis militants have pledged to take their holy war to Lebanon if ordered by their chief Abu Bakr al-Baghdadi, in videos released to promote their message.