Senior U.S. Senator John McCain paid a visit to the Libyan rebel headquarters in their eastern stronghold city of Benghazi on Friday, an Agence France Presse correspondent said.

McCain was mobbed on arrival at the courthouse in the center of the city by a crowd of about 50 people, who chanted, "Libya free, Gadhafi go away -- thank you America, thank you Obama."

Libyan rebels Thursday overran a post on the Tunisian border, marking their first advance in weeks against Moammar Gadhafi's forces as NATO warned civilians to stand clear of its bombing blitz.

The capture of the Wazin border post was cheered by several hundred rebels who raised the flag of the Libyan monarchy after some 150 to 200 pro-Gadhafi soldiers abandoned their weapons and fled into Tunisia.

Russian Foreign Minister Sergei Lavrov on Thursday warned against a Western ground operation in Libya, saying it would be an "extremely risky" action with unpredictable consequences.

Speaking in the Slovenian capital Ljubljana, Lavrov said that Russia was worried by signs of a move towards a ground conflict involving Western forces in Libya.

Two Western photojournalists, including an Oscar-nominated film director, have been killed in the besieged city of Misrata while covering battles between rebels and Libyan government forces. Two others working alongside them were wounded.

British-born Tim Hetherington, co-director of the documentary "Restrepo" about U.S. soldiers on an outpost in Afghanistan, was killed Wednesday inside the only rebel-held city in western Libya, said his U.S.-based publicist, Johanna Ramos Boyer. The city has come under weeks of relentless shelling by government troops.

A rebel official in Libya's besieged city of Misrata pleaded for Britain and France to send troops to help fight Moammer Gadhafi's forces, while a son of the strongman said he was "very optimistic" his father's regime will prevail, sources told the Agence French Presse on Wednesday.

A senior member of Misrata's governing council, Nuri Abdullah Abdullati, said they were asking for the troops on the basis of "humanitarian" principles, in the first request by insurgents for boots on the ground.

Saif al-Islam Gadhafi, son of the Libyan leader who is battling a rebellion, claimed "we didn't commit any crime against our people," in an interview with The Washington Post reported Sunday.

The 38-year-old Saif Gadhafi told the Post in an hour-long interview in Tripoli that evidence of Libyan forces firing on anti-government demonstrators is false, likening it to reports of pre-war Iraq hiding weapons of mass destruction.

At least 13 people were killed and some 50 wounded Thursday in an attack by Moammar Gadhafi's forces on the port area of Libya's third city Misrata, a rebel spokesman said.

"At least 13 people died, including women and children and four Egyptians who had attempted to be evacuated from the port," the spokesman said on condition of anonymity.

U.N. chief Ban Ki-moon on Thursday called for a "political" solution and immediate ceasefire to the conflict in Libya, at an international conference hosted by the Arab League in Cairo.

"We call for a political process so that the Libyan people can reach their aspirations," Ban, who co-chaired the meeting, told a news conference at the end of the gathering.

Libya's foreign minister expressed hopes for a "political solution" to end the two-month conflict in his country, his Cypriot counterpart said after the pair held talks on Thursday.

Abdelati Laabidi reiterated a "commitment to the initiative of the African Union and the wish for a political solution to be achieved," Cypriot Foreign Minister Marcos Kyprianou told reporters in Nicosia.

Libya's deputy foreign minister, Khaled Kaim, has accused Hizbullah of joining the ranks of the rebels fighting against Libyan leader Moammar Gadhafi’s regime.

Kaim claimed Wednesday that several members of Hizbullah are fighting alongside the rebels in Misrata, but did not provide evidence.