Buthaina Shaaban, a key aide to Syrian President Bashar Assad, has visited Norway in the first trip to Europe by a senior official in three years, her office said Sunday.

"Dr. Buthaina Shaaban visited Oslo on June 18 and 19 at the invitation of the Norwegian foreign ministry to take part in a conference," one of her colleagues told Agence France Presse.

Syrian troops backed by fighters from Lebanon's Hizbullah on Sunday launched an assault to oust rebels from the foothills of the Qalamun mountains north of the capital, state television said.

Regime forces took parts of the strategic Qalamun region near the border with Lebanon in April, but some 2,000 rebel fighters withdrew to the hills, from where they have launched guerrilla attacks.

The teenage son of an Israeli defense ministry contractor was killed on the Golan Sunday in the most serious incident on the plateau since the Syrian civil war erupted in 2011.

Israel's defense ministry and the army said the 15-year-old was killed when a blast hit the car he was traveling in with his father and another contractor, both of whom were wounded.

U.S. Secretary of State John Kerry headed to the Middle East Sunday seeking to overcome the sectarian divide in Iraq where Sunni militants seized more ground in an offensive that could rip the country apart.

Shiite fighters paraded in Baghdad on Saturday in a dramatic show of force aimed at their Sunni opponents who took control of a Syrian border crossing.

Air raids killed 16 people in Syria's Deir Ezzor province Saturday, most of them people gathered at a mourning tent for rebel Free Syrian Army (FSA) officers murdered by jihadists, an NGO said.

Warplanes "bombed the locality of Muhassen six times, killing 16 people, including three women," the Syrian Observatory for Human Rights said.

The Internal Security Forces apprehended on Saturday the members of a prostitution ring in the Mount Lebanon town of Brummana, all of whom are Syrian nationals.

"The judicial police's Morals Protection Bureau obtained information on the presence of a ring that practices and facilitates prostitution in the Brummana area,” the ISF said in a statement.

Russia and Saudi Arabia Saturday stressed the importance of preserving Syrian and Iraqi territorial integrity after talks in the Western city of Jeddah.

Riyadh and Moscow have opposing positions on the conflict in Syria, with Russia backing President Bashar Assad and Saudi Arabia supporting the rebels seeking to topple him for more than three years.

The father of a British man who left to fight in Syria said on Saturday he "wants to cry" after his son appeared in an online video aimed at recruiting jihadists.

Ahmed Muthana identified the man in the 13-minute video, entitled "There is No Life Without Jihad", as his 20-year-old son, Nasser Muthana, from Cardiff. 

Hizbullah official Mohammed Raad called on Saturday for further coordination between security agencies in the fight against terrorism, stressing that jihadists of the Islamic State of Iraq and the Levant (ISIL) will not find safe haven in Lebanon.

“The security developments in Lebanon require discreet, accurate and serious followup,” MP Raad, the head of Hizbullah's Loyalty to Resistance parliamentary bloc said.

Jihadists from the Islamic State of Iraq and the Levant (ISIL) have executed three officers of the Western and Arab-backed rebel Free Syrian Army, a monitor said Saturday.

The bullet-riddled bodies of the three were found on Friday, two days after suspected Islamist militants kidnapped them in the oil-rich eastern province of Deir Ezzor, said the Syrian Observatory for Human Rights.