Beirut: Lebanese authorities have arrested nine Sunnis suspected of planning to assassinate Syed Hassan Nasrallah, the leader of Hezbollah, security officials said yesterday.

The suspects are eight Lebanese and one Palestinian, security and judicial sources said. Their plot could be seen as an evidence of the rising tension between both sects in a country yet to fully recover from a 1975-1990 civil war.

"They had placed him [Nasrallah] under surveillance and were targeting him for pure sectarian and radical reasons," a senior political source familiar with the matter said.

A prosecution source said the suspects' motive was to defend the Sunnis "in case the tension between both sects escalates".

A senior security official said: "The plot was at an early stage. It had not reached the phase of implementation."

He said the suspects' training and ability to carry out such an attack was not clear.

The men were charged with attempting to carry out terrorist acts, the prosecution source said, adding that five other members of the same group were still at large. The eight Lebanese suspects were related to each other, officials said.

A string of bombings and political assassinations has rocked Lebanon since the February 14, 2005, killing of former prime minister Rafik Hariri.

Lebanon's Sunni and Shiites are at loggerheads over key issues dividing the country, mainly the fate of pro-Syrian President Emile Lahoud, who is under pressure to quit, and the disarming of the Hezbollah group.

Hezbollah spokesman Hussain Rahal said authorities had informed the group of the plot.

"We can confirm this," he said. "Lebanese authorities have informed us that they arrested a group accused of planning to assassinate Syed Hassan Nasrallah."

Another security source said the suspects had been planning to assassinate Nasrallah on April 28, when he is expected to attend a round of national dialogue talks with other Lebanese leaders at the Lebanese parliament.

Security forces seized an unknown quantity of weapons with the suspects, including machine guns and rocket-propelled grenades, officials said.

Nasrallah is usually accompanied by heavy security and his movements are limited. His predecessor, Syed Abbas Al Mousawi, was killed in an Israeli raid in 1992. Hezbollah's headquarters in Beirut's southern suburb, where Nasrallah also resides, are heavily guarded.