The takeover, which was aired live on local TV, happened as most of the security forces’ attention was focused on a tense demonstration against the ruling elite a few hundred metres down the road.
“We are taking over the foreign ministry as a seat of the revolution,” said Sami Rammah, a retired officer who spoke through a loudspeaker from the ministry building’s front steps.
“We call on all the anguished Lebanese people to take to the streets to demand the prosecution of all the corrupt,” he said.
An explosion at Beirut port Tuesday that is widely blamed on the incompetence and corruption of the ruling elite killed at least 158 people, wounded 6,000 and made hundreds of thousands homeless.
Rammah, who stressed the protest camp was “not against one specific person but against a system that destroyed the country”, urged the international community to boycott the government.
“We call all our Arab allies and other allied nations and the Arab League and the United Nations to consider our revolution as the real representative of the Lebanese people,” he said.
His call came amid intense diplomatic activity in solidarity with disaster-struck Lebanon and on the eve of an international donor conference.
Four days since the blast, grief gave way to rage, with a large demonstration Saturday that was reminiscent of the unprecedented nationwide and cross-sectarian protest movement that erupted in October.
Around 200 people occupied the foreign ministry compound, which lies on an upmarket street in central Beirut.
Their entry into the ministry appeared to have been facilitated by the damage the historical building sustained in Tuesday’s monster explosion.
Some of the protesters pulled the portrait of President Michel Aoun off the wall and smashed it on the ground, an AFP correspondent there said.