NATO said it will hold an emergency meeting after Ankara on Sunday accused Syria of downing a Turkish jet in international airspace, raising fears that tensions could soar in the tinderbox region.

While admitting that a Turkish F-4 phantom jet briefly strayed into Syrian territory on Friday, Turkish Foreign Minister Ahmet Davutoglu said it was clearly out of it when it was shot down.

The release of a legal team held in Libya since a visit to slain leader Moammar Gadhafi's son Seif al-Islam more than two weeks ago appears some way off despite "constructive" talks, Australian Foreign Minister Bob Carr said Sunday.

Four International Criminal Court (ICC) staff, including Australian lawyer Melinda Taylor and her Lebanese interpreter Helene Assaf, have been held in Zintan since June 7 after travelling there to help prepare Seif al-Islam's defense.

Violence in Syria killed at least 63 people on Sunday, nearly half of them troops who died in clashes with rebels, as the bloodshed reached new heights, said the Syrian Observatory for Human Rights.

At least 16 soldiers were killed in the northern Aleppo province, while one died in an attack on his vehicle in neighboring Idlib province and the rest died in fighting elsewhere in Idlib and in the provinces of Damascus and Deir Ezzor in the east.

Iran has urged Ankara and Damascus to show "restraint" over Syria's shooting down of a Turkish fighter jet, Iranian state media reported on Sunday.

Tehran "asks both sides to show calm and restraint, and hopes that with tact and tolerance and dialogue this issue will be evaluated and through a peaceful resolution, tranquility and stability will be preserved in the region," Foreign Minister Ali Akbar Salehi was quoted as saying.

The Philippines said Sunday that at least 14 immigration officers were under investigation for alleged involvement in the human trafficking of poor Filipinos to violence-torn Syria.

Immigration commissioner Ricardo David said his office was cooperating with a probe being carried out by a special government task force on trafficking, which could lead to criminal charges or the firing of officers.

Demonstrators battled police in central Tel Aviv on Saturday night in protest at what they said was excessive police use of force at a rally the previous night.

An Agence France Presse photographer saw several scuffles between police and protestors on Saturday and at least one demonstrator had a bloody face.

U.N. leader Ban Ki-moon on Saturday raised his "deep concern" about the impact of Syria's shooting down of a Turkish fighter jet with Turkey's foreign minister, a spokesman said.

Ban expressed "his deep concern about the downed Turkish military jet and particularly about the potential serious implications of this incident for the region" in telephone talks with Turkish Foreign Minister Ahmet Davutoglu, U.N. spokesman Martin Nesirky said.

A Russian ship carrying a controversial cargo of attack helicopters that Moscow repaired for Syria has re-entered Russian waters after turning back off Britain, an official said on Saturday.

The Alaed, whose cargo has greatly troubled the West amid the spiraling conflict in Syria, is due to enter the Kola Gulf, which leads from the Barents Sea towards Russia's Arctic port of Murmansk, on Sunday morning.

The International Committee of the Red Cross on Saturday condemned the killing of a Syrian Arab Red Crescent volunteer, in the fourth such incident in the country's deadly unrest.

Bashar al-Youssef, 23, was shot and fatally wounded on Friday in Deir al-Zour in eastern Syria, the two organizations said in a joint statement.

A leader of the ruling Hamas said Saturday the militant group had agreed to try anew an Egypt-brokered ceasefire with Israel, after six days of bloodshed in and around the Gaza Strip.

Hamas and "the Palestinian resistance factions will respect the truce as long as the (forces) of the occupation do the same and that's what we told our Egyptian brothers who demanded that we cease fire," Ayman Taha told Agence France Presse.