He's a white guy and his name and photo have been all over multiple media outlets from the moment this story broke.
I'd wager a bet nobody asked him to stand on a scale or next to a tape measure while he was shooting up the place but it's fair to say his height and weight weren't particularly memorable so I'd guess he's not a giant, not a midget, and not a leviathan. In other words, he's "of average build."
This scum was known to the FBI and according to social media his family is apparently full of far-left libtards who are proud of their “#resistance”.