By Brenna Owen A raging wildfire that has forced evacuations on south-central Vancouver Island has been burning at some of most severe levels of fire behaviour, a display that is “unusual” for the region, the British Columbia Wildfire Service said. An update posted by the service said the blaze, located about 12 kilometres south of Port Alberni, has been burning at rank four and five on a six-point scale. “This is a highly vigorous surface fire with torching or passive crown fire and some active crown fire,” the service said in an update on Wednesday. “This is unusual fire behaviour for wildfires on Vancouver Island.” The Mount Underwood fire was discovered Monday afternoon and has since grown to more than 20 square kilometres. Photographer and videographer Colby Rex O’Neill, who…