And I would say no. I counted my CS letter as non-science, and got the rest of my letters from microbiology profs. You'll want to check with your schools of interest, but science LORs are supposed to represent your aptitude for biomedical science. If CS aptitude indicated biomed aptitude, I'd be in at Harvard.
I don't think AACOMAS categorization mandates anything, but CS is counted as math which is not counted as science. Engineering counts as "other science."