Supporters of Shia groups Hezbollah and Amal attacked anti-government protesters in Lebanon overnight.
Video footage showed gunmen storming the main protest camp in the southern city of Tyre and attacking protesters and tearing down their tents.
Hezbollah and Amal supporters also reportedly attacked demonstrators in Beirut.
Two protesters were reportedly injured in the attack.
The official Lebanese news agency, however, said calm has been restored in the area after the attack.
On Sunday, ten protesters were injured in clashes between demonstrators and backers of Hezbollah and Amal groups in central Beirut.
Lebanon has been rocked by mass protests since last month against plans for tax increases, which quickly turned into wider grievances.
The unrest has forced Prime Minister Saad Hariri to resign, with no progress toward reaching a deal on a new government.
*Ahmed Asmar contributed to this report from Ankara