France’s national intelligence service has conclusively linked the Assad regime in Syria to a chemical weapons attack against civilians earlier this month.

The report, the first such intelligence brief made publicly available since the incident on April 4th, links the chemical substance used on the town of Khan Sheikhoun with a previous attack executed by the Syrian regime.

“We have definite sources that the procedure used to make the Sarin sampled is typical of the methods developed in Syrian laboratories,” said French Foreign Minister Jean-Marc Ayrault. “This method bears the signature of the regime, and that is what has allowed us to establish its responsibility in this attack.”

Over 80 civilians were killed in the attack, which drew attention back to the Syrian Civil War and universal condemnation from the international community. President Donald Trump directly cited the incident as justification for his cruise missile attack on Syrian regime targets.