Over the past three days, militiamen stormed the headquarters of the Interior Ministry and state-run TV and besieged the Foreign Ministry while publicly calling for the removal of Gadhafi-era officials from government posts and the passage of the so-called "isolation law," which would bar from political life anyone who held any position -even minor- under the ousted autocrat's regime.
However, analysts and democracy advocates believe militiamen are using the isolation law as a way to get rid of Prime Minister Ali Zidan, who has vowed to restore the authority of the state and disband the armed groups that have become a power unto themselves in Libya. Many of the militias have an Islamist ideology, while Zidan is seen as more secular and liberal.
"In essence this is power struggle between liberals and Islamists. This is a very dangerous turn that could force Zidan to step down," said political analyst Saad al-Arial. "Each wants to push the other aside, and the way to do so is in parliament and in the street."
Zidan is backed by the Alliance of National Forces, a bloc that holds the biggest number of seats in parliament and is led by Mahmoud Jibril, a liberal-leaning figure who served as the opposition's prime minister during the civil war that eventually led to Gadhafi's ouster and death in the autumn of 2011.
With the oil-rich North African nation still trying to write a constitution and chart its post-Gadhafi path, the alliance has been locked in a power struggle with Islamists, including the Muslim Brotherhood.
The isolation law has become a significant battleground in the rivalry. An initial version of the law presented to the parliament, known as the General National Congress, would have been an entire ruling class from politics, even figures who had minor posts or left the government decades before the uprising against Gadhafi began in early 2011. Among those who could be affected are the congress head Mohammed el-Megarif, who was ambassador to India before defecting to the opposition in 1980; Zidan, who was a diplomat until he defected at about the same time; and Jibril, who was once an aide to Gadhafi's son.
A new version of the bill, posted on the congress' official Facebook page Monday, included a new article that gives parliament powers to exempt some figures from the law in apparent attempt to prevent removal of key figures.
"This law is made by the Islamists to get rid of Zidan and his group," said al-Arial.
The head of the Brotherhood's Justice and Construction Party, Mohammed Sawan, insisted on Monday that the final version of the law "will not have any exceptions and no one will be exempted."
He told The Associated Press that talks were ongoing among all factions in parliament on the bill. He denounced the use of arms in protests connected to the law but said, "The parliament has been slow in issuing the isolation law, and there are ministry officials and ambassadors who served under Gadhafi. So protesters are demanding them to leave."
The militias are rooted in the armed brigades that arose during the civil war to fight Gadhafi's army. But since his fall, they have mushroomed in numbers and strength, operating as local powers and often as outright gangs, though they claim "revolutionary" credentials. They often run their own prisons, detaining those they consider old regime supporters or criminals.
On Tuesday, militiamen sealed off the roads to the Justice Ministry in the capital Tripoli with their gun-mounted trucks and surrounded the building. Some of the gunmen stormed inside and ordered employees to leave. They sprayed graffiti reading, "Yes to isolation of (Gadhafi) loyalists." At the same time, a group of civilians marched on the parliament building, calling for the isolation law to be passed.
Activists said the gunmen targeted the Justice Ministry after Salah al-Marghan, the minister, gave a deadline for militias to hand over detainees they are holding to the state by June.
On Sunday, about 200 armed men surrounded the Foreign Ministry building with their gun trucks, demanding a new foreign minister, the removal of ambassadors who served under Gadhafi and the closure of Libya's embassy in Moscow, which they accuse of supporting Gadhafi's regime.
"These groups don't speak for the Libyans and their will," said longtime rights advocate Hassan al-Amin, now in self-exile in London after resigning as head of human rights committee in parliament upon threats from militia. "Libyans want the political isolation in principle but through legitimate channels."
"These groups hijacked the legitimate demands of the Libyan people and want to exploit it for their interest," he said in a video clip posted on the Libya al-Mostakbal news website, which he heads.
The United Nations Support Mission in Libya urged all parties to "join the country's democratic transition," in a statement issued on Tuesday.
The militias' moves over the past days forced parliament to suspend its sessions until May 5 - delaying its consideration on the isolation law and its debate over the process for writing a constitution. Libya had no constitution under Gadhafi and was instead ruled by his political manifesto, the Green Book. Before Gadhafi's coup in 1969, Libya was a constitutional monarchy with a parliament, constitution and king. Many Libyans are calling for return of the old constitution.