The protesters demanded accountability to those responsible for the August 4, 2020 explosion that left 218 dead, some 6,500 injured and millions of dollars in damage.
Riot police and stone-lobbing protesters crashed, lit a fire and tried to storm Parliament.
The police responded by firing water cannons, water bullets and tear gas.
Relatives of the victims and Lebanese citizens in general accuse the legislators of obstructing the investigation of the disaster.
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