(Reuters) - Wind gusts near hurricane force were occurring in the Florida Keys, the National Hurricane Center said on Saturday in an update on Hurricane Irma. The storm was about 105 miles (170 km) southeast of Key West with maximum sustained winds of 125 miles per hour (205 kilometers per hour), the center said.  Irma was moving west-northwest at 9 mph (15 kph).  The center said a weather station in Vaca Key reported sustained winds of 48 mph (77 kph) with a gust to 66 mph (106 kph). Marathon, Florida, in the Keys reported sustained winds of 51 mph (81 kph) with a gust to 71 mph (115 kph). On the Saffir-Simpson wind scale, sustained winds of at least 74 mph (119 kph) are classified as hurricane strength. Irma s maximum sustained winds of 125 mph were classified as a Category Three storm.  