Armed men have surrounded Libya's foreign ministry in the capital, Tripoli, to push demands that officials who had worked for deposed leader Muammar Gaddafi's government be banned from senior positions in the new administration.
At least 20 pickup vehicles loaded with anti-aircraft guns blocked the roads on Sunday, while men armed with AK-47s and sniper rifles directed the traffic away from the building, witnesses said.
Esaam al-Naas, a Libyan military official, said there were at least 200 armed men surrounding the ministry building.
He said negotiations with the protesters were under way and that no one had entered the building.
Ali Zeidan, Libyan prime minister, said armed groups also tried to storm the ministry of interior and a state news agency on Sunday.
Zeidan urged people to help the government in resisting such armed groups. "There are people who want to destabilise the country and terrorise foreigners and embassies. Hopefully, citizens will face them," he said.
The armed group warned that their actions could spread to other ministries.
Tension between the government and armed groups have been rising in recent weeks since a campaign was launched to dislodge the groups from their strongholds in the capital.
Since Gaddafi was toppled by Western-backed rebels in 2011, oil exporter Libya has been awash with weapons and roving armed bands who are increasingly targeting state institutions.
Sunday's protest was to demand a law be passed banning officials who had worked for Gaddafi from occupying senior positions in the government. The legislation is under discussion but has yet to be approved.
"The Ministry of Foreign Affairs will remain closed until the political isolation law [against ex-Gaddafi officials] is implemented," the commander of the group told Reuters news agency.
He added that the foreign ministry had been targeted because some officials employed there had worked for Gaddafi.
Proposals on anvil
An official, who declined to be named, admitted that the armed men's demands were "legitimate" but he said it did not justify "paralysing the whole work of a ministry" and criticised the group's "extremely offensive" behaviour.
The General National Congress (GNC), Libya's highest political authority, is studying proposals for a law to exclude former Gaddafi regime officials from top government and political posts.
The proposed law could affect several senior figures in the government, and has caused waves in the country's political class.
In March, demonstrators encircled the assembly, trapping members in the building for several hours as they called for the adoption of the law.
After the siege was lifted, the attackers targeted the motorcade of Mohammed Megaryef, head of the GNC, without causing any casualties.