The Weekly Standard reports that the President said that the killer used a fully automatic weapon:

Now, over the next couple of months, we’ve got a couple of issues:  gun control.  (Applause.)  I just came from Denver, where the issue of gun violence is something that has haunted families for way too long, and it is possible for us to create common-sense gun safety measures that respect the traditions of gun ownership in this country and hunters and sportsmen, but also make sure that we don’t have another 20 children in a classroom gunned down by a semiautomatic weapon — by a fully automatic weapon in that case, sadly.