Police fired water cannons at student protesters in Albania's capital Tirana.
This, as clashes continued for a second day, with demonstrators joining a broader anti-government campaign opposed to a development project linked to US President Donald Trump's son-in-law, Jared Kushner.
Officers in riot gear clashed with youths who set up street barricades using burning trash bins.
The demonstrations began over grievances with Albania's public education system, but students later joined so-called Flamingo anti-government movement, which is calling for the resignation of Prime Minister Edi Rama over allegations of widespread corruption.
Dubbed the "Flamingo Revolution" after protesters used signs depicting the pink bird, the movement has staged months of rallies against the proposed coastal project, fuelling political tensions in Albania.