American Military Official Says Chemical Weapons Were Not Used By the Assad Regime

Says, "Something went down, but it was short of a chemical weapon"

(CNN) -- The United Nations will investigate claims by the government and rebels that either side used chemical weapons against each other in the Syrian conflict.

The United Kingdom and France have also put in requests with the U.N. to investigate the alleged use of such weapons in three cases.

U.S. President Barack Obama and other American officials have said in recent days there was no intelligence to substantiate reports that rebels used chemical weapons against government troops.