Fighting has continued to rage on between government forces and rebels close the Syrian capital.
The British-based Observatory for Human Rights said troops pursued rebels in the town of Daraya, just south of Damascus, the scene of heavy fighting over the last two days. Fifteen people died on Friday, most of them from injuries suffered in battles the day before, said the group, which relies on a network of activists on the ground.
Residents of Damascus reporting hearing loud explosions as shells fired from the Qasioun mountains overlooking the capital slammed into Daraya and the nearby suburb of Moadimiyeh.
Human rights groups say more than 20,000 people have died since the Syrian uprising against President Bashar Assad erupted in March 2011.
The bloodshed in Syria has also drawn neighbouring Lebanon deeper into the unrest - a troubling sign for a country that suffered its own 15-year civil war from 1975 to 1990 and has an explosive sectarian mix of Sunni and Shiite Muslims, Christians and Palestinian refugees, as well as deep divisions between pro and anti-Syrian factions.
Fresh clashes also broke out on Friday in northern Lebanon between supporters and opponents of the Syrian regime, killing two people and wounding 17 others, Lebanese security officials said.
The fighting in the port city of Tripoli was the latest instance of the Syrian civil war causing unrest next door in Lebanon, a country long under Syrian influence. Syria was in virtual control of its smaller neighbour for many years, posting tens of thousands of troops in Lebanon, before withdrawing under pressure in 2005.
Even without soldiers on the ground, Syria remains influential, and its civil war has stirred long-standing tensions that have lain under Lebanon's surface.
The clashes of the past few days in Tripoli represent some of the most serious fighting in Lebanon in several months. The mostly Sunni city weathered gunbattles in May, when fighting over Syria killed eight people.
In the latest clashes, gunmen from the Sunni neighbourhood of Jabal Mohsen battled armed elements from the neighbouring district of Bab Tabbaneh, which is populated mostly by followers of the Alawite sect, an offshoot of Shiite Islam. Assad comes from Syria's Alawite minority, while rebels fighting his regime are mostly Sunnis.