Some 500 people gathered in the Bab Al-Tebbaneh neighbourhood of Tripoli, a mainly Sunni Muslim city along Lebanon's northern coast, to voice support for anti-government protesters in Syria and demand the release of any refugees who could be held in Lebanon.
Gathered outside a mosque, the protesters -- who included dozens of Syrian refugees who fled to Lebanon this month -- chanted support for Daraa and Banias, two mainly Sunni regions in Syria that have witnessed deadly violence.
"With our souls, with our blood, we are loyal to Daraa and Banias," and "Down with the Syrian regime," they chanted. "We stand against the Syrian regime, the regime of Bashar al-Assad, and we stand behind protesters in Syria," said Sheikh Mazen al-Mohammed, imam of the mosque outside which the rally was held.
"We give the Lebanese government until Friday to release all Syrians it is holding or else we will organise a massive popular rally."
International rights group Human Rights Watch has documented the detention of nine Syrian men and one child since May 15 by Lebanon's security forces, allegedly for crossing illegally into Lebanon.
Unconfirmed reports, however, indicate the number may be much higher.
Human Rights Watch has urged Lebanon to release the refugees and to refrain from handing them over to Syrian authorities for fear they risk torture.
Thousands of Syrians, mainly women and children, have fled violence in their hometowns and sought refuge in north Lebanon since April, risking gunfire as they make their way across illegal border crossings.
More than 1,000 people have been killed in Syria, according to rights groups, as security forces crack down on anti-regime protests that broke out 10 weeks ago.
Lebanon has been the scene of several face-offs between rival rallies both for and against Assad, with security forces regularly dispersing the demonstrations.
Tripoli, Lebanon's second-largest city after the capital Beirut, has witnessed mainly Islamic demonstrations in support of anti-Assad protesters in Damascus.
The city has in the past few years also been the scene of intense clashes between Sunni Hariri supporters and Alawite Muslims loyal to a Hezbollah-led alliance backed by Iran and Syria.