BEIRUT (AP) -- Several hundred demonstrators angry over attacks against Sunni Muslim clerics blocked roads with garbage bins and burning tires in Beirut and other Lebanese cities on Monday, enflaming old tensions already boiling over the conflict in Syria.
The country is sharply split along sectarian lines, and the civil war next door has exacerbated those divisions among supporters and opponents of President Bashar Assad. The split is a legacy of the nearly three decades when Damascus all but ruled Lebanon, until 2005.
Gunmen supporting opposing sides of the Syrian civil war have frequently clashed, raising concerns that fighting could spread.
Assad's ally, the militant Hezbollah group, is Lebanon's strongest political and military movement and has been accused by Syria's overwhelmingly Sunni rebels of assisting Assad in his military crackdown. Assad belongs to a small branch of Shiite Islam.
Hezbollah denies any of its members are fighting alongside Assad but says several of its fighters have been killed while defending themselves against Sunni gunmen in areas along the border.
Two violent incidents in Lebanon itself have turned up the temperature.
On Sunday night, Mazen Hariri and Ahmad Fekhran, two Sunni Muslim sheikhs at Dar al-Fatwa, Lebanon's highest Sunni religious authority, were attacked by a group of Shiite men shortly after leaving a mosque in downtown Beirut. They were beaten up by Shiites in the predominantly Shiite neighborhood of Khandak al-Ghamik.
Two other Sunni sheikhs were assaulted in another Shiite neighborhood of Beirut in a separate incident.
As news of the incidents spread, dozens of people took to the streets, blocking roads in the capital and in the predominantly Sunni cities of Sidon and Tripoli in southern and northern Lebanon.
Trying to contain the fallout, Interior Minister Marwan Charbel said those responsible for the attacks were not affiliated with any party.
But many Sunnis quickly direct their anger at Hezbollah and Amal, the two main Shiite groups in Lebanon.
Lebanon's Grand Mufti, Mohammed Rashid Kabbani said the attacks were "not a coincidence."
"I'm not accusing any specific faction, but Shiite leaderships in Hezbollah and Amal ... must lift the cover on the perpetrators," he said Monday.
Hezbollah was quick to condemn the attacks and assisted in handing over the suspects to security forces.
Demonstrations had a clearly sectarian tone.
"The turban of the Sunnis is stronger than attempts at sedition," read a poster held up by protesters at a rally in the mainly Sunni Tarik al-Jdideh district in Beirut.
Regional tensions between Sunnis and Shiites have increased significantly because the Syrian civil war. Most of the rebels fighting to topple Assad are from the country's Sunni majority, while the president belongs to the Alawite sect, an offshoot of Shiite Islam.
In Lebanon, mortar and artillery shells from the Syrian side often explode in Lebanon.
On Monday, Syrian warplanes hit targets along Syria's border with Lebanon. The state-run National News Agency said the attack hit a remote area near the town of Arsal.
The shelling came just days after Damascus warned Beirut to stop militants from crossing the border to fight with rebels.
A senior Lebanese official confirmed the fighter jets' activity along the frontier, but said it was not clear if targets inside Lebanese territory were hit. The official spoke on condition of anonymity in line with regulations.
Lebanon, a tiny country with a population of about 4 million, also shelters about 360,000 Syrian refugees.
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