Nine illegal immigrants have died among some 300 abandoned by smugglers in the scorching Sudanese-Libyan desert, with the others in poor condition, Khartoum's army said Wednesday.

"They were on their way to Libya as illegal immigrants," spokesman Sawarmi Khaled Saad told Agence France Presse.

Gunmen stormed the Libyan parliament on Tuesday forcing lawmakers to postpone a vote for a new prime minister to take on the lawlessness gripping the North African nation.

The election was triggered by the resignation of Abdallah al-Thani earlier this month, who quit just five days after his appointment, saying he and his family had come under attack. 

A car bomb targeting a Libyan special forces barracks in the restive eastern city of Benghazi on Tuesday killed two soldiers and wounded another two, medical and military officials said.

The attack, which took place at the entrance to the barracks on road to the airport, appeared to have been carried out by a suicide car bomber, an army officer said, speaking on condition of anonymity.

A Libyan court said Sunday that it would appoint a lawyer for slain strongman Moammar Gadhafi's son Seif al-Islam after he insisted in a controversial hearing by video link that "God is my counsel."

Just 22 of 37 former Gadhafi regime officials being tried for a raft of alleged abuses during the 2011 uprising that ended his 42-year rule were in court for Sunday's hearing in the capital.

The second-ranking U.S. diplomat warned on Thursday during a visit to Libya that the threat of extremism is an "enormous challenge" for the North African country and the international community.

William Burns is the most senior American official to travel to Libya since an assault on the U.S. consulate in the eastern city of Benghazi killed four Americans, including ambassador Chris Stevens, in 2012.

A top U.S. diplomat was visiting Libya on Wednesday to meet government officials, amid political upheaval in the North African country, the State Department said.

Deputy Secretary of State Bill Burns was in Tripoli to meet with senior Libyan officials including interim prime minister Abdullah al-Thani and leaders of Libya's parliament, the General National Congress, the State Department said in a statement.

Bahraini authorities caught two inmates Wednesday after their escape from a main jail prompted the dismissal of the Gulf kingdom's prisons chief, the interior ministry said.

The pair who escaped on Monday were being held over their alleged involvement in Shiite-led protests in the kingdom, where the Sunni monarchy crushed a February 2011 uprising backed by the Shiite majority, according to lawyers.

Libya's constituent assembly, which has been charged with drawing up a new constitution, launched its work Monday in Al-Baida, in the country's east where violence has been rife since the 2011 revolt.

Dozens of officials, tribal chiefs and civil society representatives took part in the ceremony amid tightened security measures.

A Jihadist group in Libya released a video on Monday showing a kidnapped hostage from the Tunisian embassy pleading with the authorities in Tunis to negotiate with his captors.

The hostage, Mohamed ben Sheikh, is shown crying during the five minute video as he calls on Tunisia's president to help rescue him from his plight.

The Libyan parliament on Sunday began hearing seven candidates who are vying to replace prime minister Abdullah al-Thani who quit last week just days after his appointment.

Thani announced he was stepping down on April 13, five days after the General National Congress, or parliament, tasked him with forming a new cabinet, saying he had been the victim of an attack.