Husari confirmed on Wednesday that his production, which is still a work in progress, is a fictional short drama based on a 2013 chemical weapons attack in Ghouta.

The United States, France, and Britain have blamed Syrian President Bashar al-Assad's government for the April 7 attack, which Syrian activists said killed more than 40 people. The three countries struck suspected Syrian chemical weapons facilities in joint airstrikes a week later.

Inspectors from the Organisation of the Prohibition of Chemical Weapons collected samples on Wednesday from a new location in the Syrian town of Douma, their second visit to the area since it was hit.

The organisation said the samples would be sent to the organisation's laboratories for analysis. An earlier visit took place on Saturday after the inspectors were delayed for days from getting to the town, just east of Damascus, over security reasons.

The Syrian government and its main backer Russia have denied responsibility for the attack. They repeatedly blamed the rebels and opposition activists for possessing and deploying chemical weapons.

Russian Embassy spokesman Mikhail Sobolev said it would bring a group of 15 Syrians who they claim were filmed in "staged videos" of the alleged attack to a meeting at the OPCW on Thursday, US Time.

The OPCW visit to Douma and sample collection would allow the international watchdog to proceed with an independent investigation to determine what chemicals, if any, were used in the attack.

The watchdog is not mandated to apportion blame. The mandate of a joint UN-OPCW body delegated to investigate who may be behind such attacks has expired and Russia has vetoed its renewal. The joint body had found the Syrian government responsible for several previous attacks.

The development is part of an ongoing clash of narratives between the West on one side and Syria and Russia on the other concerning the suspected attack. Thousands of Douma residents left the town after the attack while Russian military police and Syrian security forced deployed in Douma, raising criticism from opposition activists the evidence may be tempered with.

Others have said that those Douma residents who stayed in the town under government control would be too afraid to challenge the Russian and Syrian narrative, fearing persecution.

Meanwhile, the head of the International Committee of the Red Cross said the organisation has been "flooded" with about 13,000 requests in the last six months from Syrians looking for missing family members.

Peter Maurer told a small group of journalists at UN headquarters in New York on Wednesday that before then the ICRC only had "requests in the hundreds".

He said the surge in requests is probably related to Syrians returning to places in the country where there is no active combat.

Maurer said the ICRC has also been "slightly more pro-active" on the issue of missing Syrians.

He said the requests have come from all areas of Syria, neighbouring countries and even globally.

As for successful reunifications, Maurer said "numbers are in the tens to fifties."

AP