Security sources said at least one soldier was wounded when the protesters threw stones at security forces in the Mar Makhaeil area of southern Beirut, where the protesters had blocked the road with burning tyres.

Protesters also used blazing tires to block the main road between Beirut and the airport, live television pictures showed.

"We lost one of our youths," one of the Amal officials told Reuters, giving the victim's name as Ali Hassan Hamza.

Later in the day a second person was reported killed, a security source said.

Protests spread in Beirut after the activist was shot dead when the army moved to break up a demonstration against power cuts.

The Amal movement is part of an opposition alliance that has been locked in a power struggle for more than a year with the Western-backed government of Prime Minister Fouad Siniora.

Tensions are running high between supporters of the rival camps, whose followers fought lethal street battles a year ago.

Soldiers deployed in the area - near the site of a shooting that triggered Lebanon's 1975-90 civil war.

The army is widely viewed as neutral in the political conflict - the worst since the civil war - and has played a policing role to contain tensions between supporters of the rival sides.

Labour unions held protests last week to demonstrate against high prices.

Reuters © 2008