Security forces fired tear gas and clashed with stone-throwing demonstrators Saturday in Lebanon's capital amid mounting fury over the massive explosion that devastated much of the city and killed nearly 160 people.
Dozens were still missing and around 5,000 people injured.
Activists who called for the protest, set up symbolic nooses at Beirut's Martyrs' Square to hang politicians whose corruption and negligence they blame for Tuesday's blast.
The explosion was fueled by thousands of tons of ammonium nitrate that had been improperly stored at the city's port for more than six years.
Apparently set off by a fire, it was by far the biggest blast in Lebanon's troubled history and caused an estimated $10 billion to 15 billion in damage, according to Beirut's governor.
It also destroyed 6,200 buildings and left hundreds of thousands of people homeless.
As the protest got underway, small groups of young men began throwing stones at security forces.
Near parliament, riot police fired tear gas at protesters who tried to jump over barriers that closed the road leading to the legislature.
The protesters later set on fire a truck that was fortifying barriers on the road leading to parliament.
At least four people were hurt in the clashes, according to the Red Cross.
Some protesters have also taken over the foreign ministry building, which was left empty after Tuesday's gigantic blast. They said that it would be the headquarters for a "revolution" and called on the current government to resign.
The gathering at Martyrs' Square and outside the parliament building and government headquarters came amid popular anger against Lebanon's political leadership.
The country's ruling class, made up mostly of former civil war-era leaders, is blamed for incompetence and mismanagement that contributed to Tuesday's explosion.