The United States has confirmed the Syrian regime carefully planned the chemical weapon attack on civilians that killed 1,429 people, including 426 children.
Secretary of State John Kerry said that a U.S. chemical weapons assessment has revealed that Syrian regime personnel were present at the site of the attack for three days, making preparations by putting on gas masks, News24 reports.
Kerry also claimed the U.S. intelligence has found out that the locations from where the rockets were launched were controlled by Assad's regime.
The information was publicly released in an intelligence report by Obama's administration on the deadly attack in Syria.
Meanwhile, President Barack Obama has been preparing for a possible military strike in a tough response to Syria for breaching international laws on use of chemical weapons.