The Tunisian government will decide by Saturday whether to allow or ban Salafists from holding their annual congress, the interior minister said on Friday, warning however "death threats" from radical Islamists will not be tolerated.

"The final decision will be taken today or tomorrow," Lotfi Ben Jeddou told Kalima radio.

The United States on Thursday blacklisted the leader of the militant Al-Nusra Front fighting the Syrian regime, as well as four top Syrian government officials, including the defense minister.

Al-Nusra's chief Abu Mohammed al-Jawlani was designated a global terrorist by the U.S. State Department, which said he had been tasked by al-Qaida in Iraq with installing Islamic sharia law across Syria.

Documents and torture equipment found in Syrian security buildings in rebel-held Raqa show detainees were tortured when President Bashar Assad's regime held sway over the city, Human Rights Watch said on Friday.

A team of researchers working for HRW toured Raqa in northern Syria in April, a month after the city fell into rebel hands, and found the incriminating evidence, the New York-based watchdog said in a statement.

Syrian rebels seized three U.N. peacekeepers in the Golan Heights in the third abduction in two months in the ceasefire zone between Syria and Israel, the U.N. said Thursday.

The abduction of the three observers came as the United Nations struggles to persuade the Philippines to keep its troops in the Golan force, which has been hit by growing fallout from the Syrian civil war.

A U.S. soldier convicted of killing five of his colleagues in Iraq in May 2009 was sentenced to life behind bars Thursday and dishonorably discharged.

Army Sergeant John Russell was convicted earlier this week over the murders at a clinic for soldiers suffering from war-related stress at Camp Liberty, the largest U.S. base in Iraq.

The Turkey-based Syrian National Coalition on Thursday said regime forces have attacked the village of Khirbet Suda in Homs province and murdered at least 18 people.

"Victims were either killed by execution at gunpoint, or slaughtered with knives," a statement said.

Jordan's foreign ministry said Thursday Amman will host a meeting of the so-called "Friends of Syria" group next week to discuss latest developments in Syria's civil war.

Spokeswoman Sabah Rafei told Agence France Presse the "foreign ministers of Jordan, Saudi Arabia, the United Arab Emirates, Egypt, Qatar, the United States, Britain, France, Turkey, Germany and Italy will meet in Amman" on Wednesday.

U.N. leader Ban Ki-moon has expressed concern to Israel's Prime Minister Benjamin Netanyahu over restricting access to holy sites in East Jerusalem, a U.N. spokesman said Thursday.

Ban spoke with Netanyahu and Palestinian president Mahmoud Abbas on efforts to relaunch the deadlocked peace process, said deputy U.N. spokesman Eduardo del Buey.

Iran should take part in an international conference agreed by Moscow and Washington to help broker an end to the Syria conflict, Russian Foreign Minister Sergei Lavrov insisted in an interview broadcast Thursday.

Lavrov told Lebanese television that Russia believed the conference, which he and U.S. Secretary of State John Kerry announced in Moscow last week, should include Iran, a key Syria ally, while stressing that this had not been agreed.

President Moncef Marzouki called on leaders of Tunisia's radical Salafist movement on Thursday to reject armed violence, saying during a meeting of "national dialogue" that the nation faced a terrorist threat.

"I am waiting for a clear condemnation of terrorism from the Salafist sheikhs in Tunisia," he said, adding that the state was "determined to act against the dangers and to use all the military and security means at its disposal."