>>>TRIPOLI, LEBANON - Clashes on both sides of the Syrian-Lebanese border have raised fears Syria's civil war may be spreading into Lebanon. Fighters have included Lebanon's Hezbollah, which supports the Syrian government, and Syrian rebel factions. In the latest incident, gunmen on Tuesday killed three Lebanese soldiers near the border and fled to Syria.

Sectarian tensions in Lebanon rose after the clashes. They took place in the northern city of Tripoli between Sunni Lebanese who support the Syrian rebels and Alawite Lebanese who support the Syrian government, which is dominated by the same offshoot of Shi'ite Islam.

In Beirut, two rockets hit a largely Shi'ite suburb Sunday - a day after Hezbollah's leader, Sheikh Hassan Nasrallah, vowed to prevent the fall of the Syrian government and to send tens of thousands of fighters to Syria if necessary.

Lebanon, recalling its own civil war, has managed to maintain basic calm and stability though this might be be changing, says Paul Salem of the Carnegie Middle East Center.  
 
“The tensions in Syria are beginning to introduce increasing pressures on Lebanon and we might be entering a more difficult period,"Salem said.
 
Hezbollah forces are now fighting alongside Syrian government troops in a major offensive against rebels in Qusair, which lies along the highway linking Damascus to the Mediterranean.

Beirut-based political analyst Kamel Wazne says Hezbollah's future is closely tied to the Syrian government's.

"I think Hezbollah, they feel that Syria is a strategic ally and the regime of President Bashar al-Assad is in a strategic co-existence. Any collapse of that regime means a weakness for the resistance [to Israel] and for Hezbollah," Wazne said.

On the rebel side, the Syrian conflict is drawing in Sunni fighters from Lebanon and around the region.  Rising foreign arms shipments to both sides are raising fears of a wider conflict.  Increasingly lethal arms, such as Scud missiles and deadly chemicals, are reportedly being used.

Wazne says negotiations leading to a political solution eventually will be necessary to stop the fighting, though he does not believe this will occur soon.

"But the healing is going to be a very long process and probably will never happen. Syria is going to be a very divided country. The level of death and destruction and the level of hatred, it's going to be a very long time before it heals itself," Wazne said.

Paul Salem says Syria could end up divided along sectarian and communal lines like Lebanon and Iraq.

"Of course there is tension, there is conflict, but both Lebanon and Iraq have had these same conflicts and tensions and they've found, at least in the Lebanese case so far, a way to handle it," Salem said.

Nevertheless, he says a prolonged conflict will widen sectarian divides across the region and could spark unexpected, deadlier consequences.