Although Watsonville fire investigators are still working to determine what caused yesterday’s fire at the 85 year-old Stag Hotel to start, they do believe it began in the lobby. The West Beach Street fire was called in around 5:45 p.m. A number of people were injured as a result of the fire, 5 of them critically, and 2 of those are reportedly still in the hospital. The entire building was declared uninhabitable after the fire.