By Dominic Evans
BEIRUT (Reuters) - At least two people were killed in heavy fighting between rival Sunni Muslim gunmen in Beirut on Monday, medical and security sources said, in the latest violence fuelled by tensions over the uprising against Syrian President Bashar al-Assad.
The clashes followed the killing of an anti-Assad Sunni cleric and his colleague at an army checkpoint in north Lebanon on Sunday, triggering angry protests in Sunni districts of northern cities and the capital.
Demonstrators blocked roads and burned tires in the northern province of Akkar where Sheikh Ahmed Abdul Wahid, a prominent critic of Assad, and Muhammed Miraib were shot. Security sources said soldiers opened fire as their car sped through a checkpoint without stopping.
Protests over the shooting spread on Sunday night to Beirut where gunmen firing rocket-propelled grenades and machineguns clashed in the mainly Sunni Muslim district of Tariq al-Jadideh - some of the fiercest battles since sectarian street battles four years ago brought Lebanon back to the brink of civil war.
A Reuters cameraman said shooting could be heard from 10 p.m. (1900 GMT) until nearly 5 a.m. (0200 GMT) on Monday.
"This is a real war," resident Mohammad Saab said on Monday after the shooting died down. "We were sitting at home with our children, then we heard gunfire, we did not know who was shooting at whom."
Security sources said the fighting pitted gunmen from the Future Movement, loyal to anti-Syrian former Prime Minister Saad al-Hariri, against the pro-Syrian Arab Movement Party headed by Shaker Barjawi.
The state news agency said two people were killed and 18 wounded. Security sources put the death toll at three - two of Barjawi's supporters and one from the Future Movement - along with nine people wounded.
Reuters Television footage from the neighborhood showed burnt-out cars on the street. Bullet holes marked the walls of Barjawi's party headquarters.
Many of Lebanon's Sunni Muslims sympathize with the Sunni-led uprising in Syria against Assad, whose father sent forces into Lebanon during its 1975-1990 civil war. The Syrian army finally pulled out in 2005 under international pressure.
But Assad retains powerful allies in Lebanon, including the Shi'ite Muslim militant movement Hezbollah and its pro-Syrian Christian partners in Prime Minister Najib Mikati's government.
Mikati appealed for calm on Sunday. "The government is determined to continue to shoulder its national responsibilities amid this critical period in Lebanon and the region, and it will take all measures necessary to preserve civil peace," he said in a televised statement.
Heavy fighting in the northern port city of Tripoli last week involving Sunni Muslim fighters, Alawite supporters of Assad and the Lebanese army left at least eight people dead.
The violence prompted four Gulf states - Bahrain, Qatar, the United Arab Emirates and Kuwait - to warn their citizens on Saturday to stay away from Lebanon.
Streets in Tripoli were mainly deserted on Monday, after Sunni religious leaders called for three days of mourning.
Funerals for Abdul Wahid and Miraib were due to be held later on Monday in Akkar province.
(Additional reporting by Issam Abdallah; Editing by Mark Heinrich)