PHOENIX (AP) -- Aided by slowing winds and increased humidity, firefighters made progress Tuesday against a 9,500-acre grass and brush fire northeast of Phoenix near Bartlett Lake, a spokesman said.
Firefighters cut a fuel-free barrier line around about three-quarters of the Bart fire after temperatures and winds dropped overnight. A rise in the humidity levels cut back fire activity but also halted firefighters' efforts to burn away vegetation near their lines, said Wendell Peacock, a spokesman for the fire crews.
''We're in a lot better shape now than we were yesterday,'' when 35 mph winds and triple-digit temperatures pushed the blaze, Peacock said. ''It was terrible conditions to try to fight a fire.''
By Tuesday morning, he said, firefighters ''were hard-pressed to find either smoke or fire.''
Peacock said the fire was more than 20 percent contained. Firefighters hope to have it fully contained by Friday night.
A $5,000 reward has been offered for information leading to the arrest and conviction of whoever started the fire, Peacock said.
Firefighters were concentrating on the hot spots _ along the east flank _ trying to keep the fire away from the Verde River and Bartlett Lake, Peacock said.
The fire was fueled by grasses that grew lush this spring from ample winter rains but have since dried out. Drought conditions remain, Peacock said.
About 340 firefighters and support staff, including 12 elite Hotshot crews and two helicopters, fought the blaze. One heavy air tanker and two single-engine tankers were on standby, Peacock said.
Early on, the fire, which began Sunday, threatened a number of buildings and recreational sites at Bartlett and Horseshoe lakes were closed Sunday night.
The Bartlett Lake and Horseshoe Dam roads, which form the fire's east and west boundaries, remained closed. Firefighters also used a burned out area from a previously contained fire as part of their containment line.