The Latest: International probe of sarin attack underway

The Latest on developments regarding Syria (all times local):

1:25 p.m.

An international team set up to apportion blame for chemical weapons attacks in Syria has started investigating the deadly April 4 sarin gas attack in Idlib province.

Director-General of the Organization for the Prohibition of Chemical Weapons Ahmet Uzumcu told The Associated Press on Friday that the team is already working and he was due to speak to its leader later in the day.

The probe by experts from the Organization for the Prohibition of Chemical Weapons and the United Nations will come under intense scrutiny amid widespread claims that Syrian President Bashar Assad's regime was responsible for the deaths of dozens of men, women and children in the town of Khan Sheikhoun. Assad denies responsibility.


11:05 a.m.

Russia's representative at the Syria talks says the "de-escalation zones" will be closed to military aircraft from the U.S.-led coalition.

Alexander Lavrentyev's comments Friday come a day after talks in Kazakhstan, where Russia, Iran and Turkey agreed to establish the zones in Syria. Under the Russian plan, President Bashar Assad's air force would halt flights over the designated areas across the war-torn country.

Lavrentyev suggested that all military aircraft, including Russian and Turkish, are prohibited. Full details of Thursday's agreement have not yet been released.

Lavrentyev, whose remarks were carried by Russian news agencies, said U.S.-led coalition aircraft would be able to operate against the Islamic State group in specific areas, but the "de-escalation zones" were now closed to their flights.

The agreement is the latest attempt to reduce violence in the Arab country.