The number of wildfires burning across central Alberta rose to 100 Tuesday, with 36 of them considered out of control, UPI quoted fire officials as saying. However, optimism rose among firefighters as 60 mph winds that had been helping the fires in the past few days had died down by at least half, officials said at an Edmonton news conference. Provincial Wildfire Information Officer Rob Harris said some 260,000 acres had been burned, more in the past few days than all of last year, the Canadian Broadcasting Corp. reported. Calgary's fire department sent 116 firefighters and 12 pieces of equipment to help around the badly burned town of Slave Lake, which was completely evacuated Sunday. At least one-third of the town 150 miles north of Edmonton was completely destroyed by flames. Harris said the firefighting effort involves 120 helicopters, 20 air tankers and hundreds of land vehicles. Tuesday morning, 124 firefighters arrived to help from neighboring British Columbia and 200 more were expected Wednesday. Ontario also sent 80 firefighters, the National Post reported. The rash of fires has been attributed to extremely dry conditions, with humidity as low as 15 percent, high winds and temperatures around 70 degrees, provincial emergency officials said. So far, there have been no reports of fatalities.