By Barbara Starr and Elise Labott
CNN has learned new details about what is contained in the U.S. intelligence assessment that alleges the Syrian regime was behind a deadly chemical weapons attack outside Damascus, Syria, last week.
According to senior U.S. officials, the assessment contains evidence showing senior regime officials making preparations for a massive chemical attack in the area where the incident occurred - the evidence is part of a "body of intelligence beforehand" that links the regime to the attack, as one of the officials described it.
It also includes evidence of senior regime officials discussing the attack afterward, acknowledging a realization the event was already getting massive attention and discussing that it would be wise to lay low for a while and refrain from launching such massive chemical attacks in the near future, the officials said.
In addition, the intelligence shows there was increased intensive shelling in the area after the attack, the officials said.
By Barbara Starr
CNN Pentagon Correspondent
CNN has learned the United States has intercepts of conversations among top Syrian military officials discussing the chemical weapons attack after it took place last week, according to a U.S. official.
The intercepts form a key basis for the conclusion that the Syrian regime was behind the attack. But another crucial piece of evidence about what type of chemicals may have been used remains to be determined. Tissue samples and other medical and forensic evidence taken from victims has not yet been fully analyzed, the official said. One source familiar with the latest intelligence said getting that information would provide the strongest case for the use of chemical weapons.
CNN has previously reported Israeli military intelligence provided the United States with intercepts between Syrian military commanders discussing the movement of chemical weapons to the area of the attack before it happened, according to a diplomatic source.
The administration has said it would release a declassified version of its intelligence assessment about last week's attack outside Damascus. White House spokesman Josh Ernest said Thursday the declassified version is not yet complete but should be released by the end of the week.