TRIPOLI  - Gunmen demanding the expulsion of officials from the ousted Moamer Kadhafi regime surrounded the justice ministry on Tuesday, stepping up an action started at the foreign ministry, an official said.

"Several armed men in vehicles equipped with anti-aircraft guns surrounded the ministry of justice," Walid Ben Rabha, head of the ministry's information department, told AFP.

"They asked the minister and staff present to leave their offices and close the ministry." Dozens of gunmen in Tripoli making the same demand have kept Libya's foreign ministry under siege since Sunday, paralysing its work. Libya's interior ministry and the national television station have also been attacked. On Monday, angry police officers firing their guns in the air stormed the interior ministry demanding higher wages.

Prime Minister Ali Zeidan has denounced the encircling of the foreign ministry and other such attacks.

On Sunday, he appealed to Libyans to support the government in resisting armed groups "who want to destabilise the country and terrorise foreigners and embassies," but said the government would "not come into confrontation with anyone".

Gunmen have said their siege of the ministries would be lifted when their demands are met by a vote in the General National Congress - Libya's highest political authority - on a bill calling for the expulsion of former regime employees.