United Nations' inspectors have arrived in Damascus on a mission to investigate the alleged use of chemical weapons in the country.
They arrived in the Syrian capital on Saturday after the government vowed to fully cooperate with the experts.
Led by Swedish arms expert Aake Sellstroem, the UN team's mission will be limited to investigating the alleged use of chemical weapons in three areas, in particular the March 19 incident in Khan al-Assal that President Bashar al-Assad blames on rebels fighting to overthrow the regime.
The attack in Khan al-Assal killed at least 26 people, including 16 Syrian soldiers.
The UN has not yet identified two other sites where investigations are to be carried out, AFP news agency said.
The mission had been repeatedly delayed earlier this year amid differences with Assad's regime over the scope of the probe.
The government and the rebels accuse each other of using chemical weapons and the regime insists that it has nothing to hide. The Syrian opposition says the investigators can have full access to sites under its control where chemical weapons are alleged to have been used.
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The UN team arrived at the Four Seasons hotel in the Syrian capital to begin their mission which UN officials have announced will last two weeks, AFP said.
Al Jazeera’s Nisreen El-Shamayleh, reporting from Amman, said that there were concerns about the value of the investigation as the team would only be able to assess whether chemical weapons had been used in certain areas, but it would not be able to reveal who was responsible for the attacks.
“The investigation has such a limited mandate,” she said.
“However, UN says that any investigation to the alleged use of chemical weapons inside Syria would serve as a deterrent in the future for either side, rebels or government, to use these weapons again.”