State Department spokesperson Heather Nauert has stated that the United States believes Russia and Syria have been "sanitizing" the site of probable chemical attack in the Syrian city of Douma.
"We can confirm that the OPCW [Organization for the Prohibition of Chemical Weapons] team has still not been able to enter Douma in Syria… We believe it is an effort to conduct their own staged investigations. Russian officials have worked with the Syrian regime, we believe, to sanitize the locations of those suspected attacks and remove incriminating evidence of chemical weapons use," she said.
Nauert also said that "credible people on the ground…have indicated that they have been pressured by both Russia and Syria to change their stories."
On April 17, it was reported that Damascus had allowed OPCW experts to enter Douma, and that specialists had arrived in the city. The OPCW has not yet confirmed any evidence of a chemical attack.