What’s the evidence of Syrian chemical weapons attack?

Story highlights

Kerry says the U.S. has declassified "unprecedented amounts of information"

The U.S. points to "concrete" evidence, intercepts, "multiple streams of information"

Britain, France, and Germany come to similar conclusions

Putin calls for "a deep and specific probe containing evidence that would be obvious"

CNN  — 

U.S. Secretary of State John Kerry calls it proof “beyond any reasonable doubt.” Defense Secretary Chuck Hagel says it’s “very clear.”

President Barack Obama says the United States has “high confidence” that Syria used chemical weapons – the strongest position the U.S. can take short of confirmation.

Britain, France, and Germany say their intelligence backs up the same conclusion.

But despite all the talk about conclusive intelligence, questions remain. A declassified report by the White House does not divulge all details of the evidence the United States is looking at. And it remains unclear what the “streams of intelligence” cited in the report may be and how they were collected.

Russia insists there’s no proof. Russian President Vladimir Putin said he wants to see evidence that would make the determination “obvious.”