By: Paige Kollock

A Lebanese soldier patrols the Bab al-Tabbaneh area of Tripoli, Lebanon.

TRIPOLI, Lebanon | The violence in Bab al-Tabbaneh, a desperately poor neighborhood in Tripoli, Lebanon, is so bad that trash collectors won't even come to clean the streets. Massive piles of garbage now lie in the sidewalks. The stench is unbearable.

Still, the fighting between this neighborhood and its historic rival, Jebel Mohsen, has only intensified.

In the past week at least 16 people were killed and some 130 injured in fighting between pro- and anti-Syrian factions that inhabit these two communities. Early Sunday morning, the crackle of sniper fire could be heard on Syria Street, just behind the front lines.

"We can't sleep at night," said Um Mohammed, 63. She lives on Syria Street with her three daughters and their families, and says she is in constant fear.

"We stay in the kitchen. Sometimes we hide in the bathroom," she said. Their house was recently hit by sniper fire from Jebel Mohsen. She says they don't dare go outside.

"If we have any lights in our home we turn them off and stay in the dark. ... We prefer to die in our house, rather than die in the streets. That's what's happening to us because we live on the front lines. Our house is very dangerous."

Um Mohammed points to bullet holes in her house.

The Lebanese Army has been deployed to keep the peace, but one of its units recently came under gunfire. On Sunday, soldiers arrested gunmen and seized arms in an effort to restore order to the port city.

The rift between the two communities dates back to Lebanon's 15-year civil war that ended in 1990. Bab al-Tabbaneh, like most of Tripoli, is a Sunni Muslim neighborhood. Jebel Moshen is Alawite, the same minority sect as Syrian President Bashar al-Assad. The neighborhoods are separated by a river, with Jebel Moshen facing Bab al-Tabbaneh from the top of a hill.

In Tripoli. Alawites number approximately 40,000-60,0000, compared to the city's 200,000 Sunnis.

The antagonism between these Lebanese groups rooted in and reflects tensions that have long played out on a bigger scale in Syria.

"It's an old wound," said Harrouk. "There are some residents who lost their children, there are people who have been in jail for five, six, even 10 years," referring to an incident in 1986 when Syrians, who were controlling Lebanon at that time, arrested hundreds of people from Bab al-Tabbaneh, some of whom were found dead in the streets shortly thereafter, purportedly shot by Syrians.

Garbage lies in piles in the Bab al-Tabbaneh neighborhood. Photos by Paige Kollock.

Poverty also plays a role. Bab al-Tabbaneh is extremely poor and a bastion of conservative Islamic Sunnis in Lebanon. Tripoli is the birthplace of Lebanon's Salafi Movement, a puritanical and restrictive Sunni movement.

On Syria Street in Bab al-Tabbaneh, Lebanese soldiers looked on as a solitary woman frantically packed her possessions into the trunk of a car. The street was filled with men, mostly fighters, who sat together in plastic chairs, sharing information via walkie-talkies. Plastic tarps hung across some streets, so snipers from Jebel Mohsen cannot see their movements. One store owner knocked out a part of his shop's back wall so patrons can enter from behind, without risking sniper fire.

Nader al-Ghazel, a municipal official, has called on a ceasefire. "It is as if some [parties] want to keep this city a 'mailbox' to send local and regional [messages]."

We'll have more about the spillover effect in Lebanon from fighting in Syria on Monday's NewsHour. View more World coverage.