France says analysis shows Syrian regime behind sarin attack

France’s foreign minister said on Wednesday that the chemical analysis of samples taken from a deadly sarin gas attack in Syria earlier this month “bears the signature” of President Bashar Assad’s government and shows it was responsible for the deadly assault.

According to Foreign Minister Jean-Marc Ayrault, France came to this conclusion after comparing samples from a sarin attack in Syria from 2013 that matched the new ones.

The findings came in a sixpage report published Wednesday.

The Kremlin promptly denounced the French report, saying the samples and the fact the nerve agent was used are not enough to prove who was behind it. Assad has repeatedly denied that his forces used chemical weapons and claimed that myriad evidence of a poison gas attack is made up.

But Ayrault said France knows “from sure sources” that “the manufacturing process of the sarin that was sampled is typical of the method developed in Syrian laboratories.”

“This method bears the signature of the regime and that is what allows us to establish its responsibility in this attack,” the top French diplomat added, saying that France is working to bring those behind the “criminal” atrocities to international justice.

France’s Foreign Ministry said blood samples were taken from a victim in Syria on the day of the April 4 attack in the opposition-held town of Khan Sheikhoun in Idlib province in which more than 80 people were killed.

Environmental samples, the French ministry said, show the weapons were made “according to the same production process as the one used in the sarin attack perpetrated by the Syrian regime in Saraqeb” on April 29, 2013.

Ayrault also said that French intelligence services showed that only Syrian government forces could have launched such an attack – by a bomber taking off from the Sharyat airbase.