(Corrects number of homes threatened from 6,800 to 68,000) (Reuters) - Wildfires burned across Southern California for a third day on Tuesday. Following are some key numbers: * Nearly 20 fires reported since Sunday, from Santa Barbara to the Mexican border * More than 500,000 people evacuated * More than 1,250 homes lost in San Diego, 68,000 homes threatened state-wide * Two people dead, around 40 injured, including at least 18 firefighters * 300,000 acres (121,000 hectares) burned * Seven Southern California counties declared disaster areas * Hot winds gusting up to 70 mph (113 kph) * About 6,000 firefighters battle flames
