PLEASANTON -- A fast-moving brush fire Thursday afternoon along the Pleasanton Ridge caused hundreds of evacuations in Pleasanton and Sunol before residents were allowed to return home later in the evening.The Canyon Fire started around 1:30 p.m. on the Kilkare side of the ridge and quickly spread up and over the top of the ridge line, and down toward Foothill Boulevard in Pleasanton prompting evacuations along Kilkare Road and Golden Eagle Estates."You really don't understand it until you come to the moment and then you're standing there and you have to leave your house and you think, 'where am I going to go? What am I going to take?'" said Zoltan Piskor.Fire dispatchers said the original location was above the 4900 block of River Rock Hill Road.The Alameda County Fire Department said as of 4:30 p.m. forward progress of the fire had been stopped. As of 7 p.m., about 71 acres had burned.Two firefighters were injured on this fire one was hit by a falling tree after a water drop. The other suffered heat exhaustion. Both were taken to a hospital and are expected to be OK.