The first shipment of chemical weapons has left Syria as part of an international deal to eliminate the country's chemical arsenal.
Inspectors from the Organisation for the Prohibition of Chemical Weapons (OPCW) say nine containers were loaded on to a cargo ship at the northern Syrian port of Latakia. The vessel left port escorted by Russian and Chinese warships.
Removing the most dangerous chemicals is the first step of a UN-backed deal to eliminate Syria's chemical arsenal.
A previous bid to collect the materials was aborted after Syrian officials failed to deliver the toxic chemicals to the collection point in Latakia, the BBC reports
The hazardous cargo is due to be taken to Italy, where it will be loaded onto a US Navy ship and shipped to international waters for destruction in a specially created titanium tank on board.
The agreement was brokered by the US and Russia after rockets filled with the nerve agent sarin were fired at three towns in the Ghouta agricultural belt around the Syrian capital Damascus on 21 August. Hundreds of people were killed in the attacks.
In a statement on Tuesday, the UN confirmed that a small number of containers with "priority one chemical materials" were on board the Ark Futura cargo ship, one of two vessels in charge of collecting the materials. They will wait in international waters for additional chemicals to be delivered to Latakia for collection.
The UN told the BBC that the chemicals came from two Syrian sites, but would not specify their locations.
The OPCW did not disclose what percentage of Syria's toxic arsenal of around 1300 tonnes of weapons and precursors had been removed.
Captives executed, say activists
Activists in the northern Syrian city of Aleppo say militants linked to al-Qaeda have summarily executed at least 50 captives.
The dead are said to include medics, local journalists and members of rival rebel groups, the BBC reports.
The alleged killings by the Islamic State in Iraq and the Levant - known as Isis - cannot be independently confirmed, but there have been persistent clashes in northern Syria between rival factions in the rebellion against President Bashar al-Assad.