US intelligence intercepts communications between Syrian military and chemical experts

A senior US official confirms that the US military and intelligence community has intercepted communications featuring Syrian military and chemical experts talking about preparations for the sarin attack that took place in Idlib last week.

The intercepts were part of an immediate review of all intelligence in the hours after the attack to confirm responsibility for the use of chemical weapons in an attack in northwestern Syria, which killed at least 70 people. 

US officials have said that there is "no doubt" that Syrian President Bashar al-Assad is responsible for the attack. The US did not know prior to the attack it was going to happen, the official emphasized. 

So far there are no intelligence intercepts that have been found directly confirming that Russian military or intelligence officials communicated about the attack. The official said the likelihood is the Russians are more careful in their communications to avoid being intercepted. 

The Russian and Syrian governments have so far both denied involvement in the chemical attack.