The day started with funerals for some of the 158 people killed by Tuesday's enormous explosion, believed to have been caused by incorrectly stored chemical fertiliser. The funerals were followed by the largest anti-government protest in months.
With security forces focused on a large gathering at the Martyrs' Square protest hub, a group led by retired army officers entered the foreign ministry and declared the building to be the "headquarters of the revolution".
The takeover lasted barely three hours.
Large numbers of army reinforcements using rubber bullets and tear gas drove out the roughly 200 protesters..
At one point, protesters had stormed or taken over four key official buildings.
"We are officially at war with our government," said activist Hayat Nazer, as tear gas filled the air in downtown Beirut.
"This is war."
Energy ministry the focus of popular anger
Separate groups of protesters stormed the economy ministry, the Association of Banks in Lebanon and the energy ministry before being forced out by the army shortly afterwards.
The energy ministry is the focus of particular anger from the population, which has in recent months been subjected to worse than ever power cuts due to the de facto bankruptcy of the state.
"They ruled Lebanon for 30 years, now Lebanon is ours," said one protester speaking on live Lebanese television broadcasts.
Well before midnight however, protesters had been dispersed and security forces deployed across the city, where the broken glass and rubble from Tuesday's disaster mixed with the smoking remains of a night of rage.
