(CNN) -- A quick summary of the British intelligence report on the use of chemical weapons in Syria, distributed as the House of Commons began debate over possible military action on Thursday:
-- It is "highly likely" that government troops carried out the reported August 21 chemical attack outside Damascus. "It is not possible for the opposition to have carried out a [chemical weapons] attack on this scale," the document states.
-- That attack killed at least 350 people, the report states. Syrian opposition reports have put the toll at more than 1,300.
-- The government concluded with "the highest possible level of certainty" that Syrian government troops had used chemical weapons in smaller-scale cases 14 times before. "We think that there have been other attacks although we do not have the same degree of confidence in the evidence."
-- Using a combination of public accounts and intelligence, the government has found "no credible intelligence or other evidence" to back up the Syrian government's allegation that opposition forces used chemical weapons against its troops.
-- The report concludes "that there are no plausible alternative scenarios to regime responsibility" for the August 21 attack. While "a number" of rebel groups have sought to obtain chemical weapons, "none currently has the capability to conduct a CW attack on this scale."