(Covers information from the D.C. comics)
Saguaro Wells was a small town in Nevada with a population of only 472. Leon Kennedy was summoned to Saguaro Wells by Sheriff Carey following the disappearance of eight people and the death of the Sheriff's own son, Wayne. The townspeople described the assailants as batlike creatures of human proportions, and Leon, a dedicated freedom fighter after the destruction of Raccoon City, was certain that Umbrella was behind the whole thing.
Sure enough, it turned out that Umbrella had established another one of its hidden research laboratories in the hills outside of Saguaro Wells, where a team of scientists headed by the unquestionably insane Dr. Callos was experimenting on residents that their bat monsters, had abducted from town. Thanks to the efforts of Leon and the US Air Force, the lab was destroyed and the experiments stopped.