The Prison Fire burning in the Santa Catalina Mountains is 50 percent contained, according to the U.S. Forest Service.
The fire continues to burn in rocky, rough terrain, making it difficult to fight, but crews are making progress.
Accurate GPS mapping reduced the burned acreage from an estimated 280 acres to 270.
Full containment is expected by Saturday night.
Smoke is occasionally visible over the fire as it burns sources that crews are not able to reach. Some of those internal sources of flames are being allowed to burn out if fire managers determine there is little danger that the fire will escape fire lines.
The Catalinas remain open for recreation, but the public is reminded to avoid areas where incident tape is placed so that they do not interfere with fire crews.
Fire restrictions remain in place, which ban the use of camp fires, smoking, target shooting and the use of welders.
Gas stoves, lanterns and heaters with shut off devices are allowed in some areas.
For more information about the restrictions and fire danger, visit http://wildlandfire.az.gov or call the toll free Southwest Fire Restrictions Hotline at 1-877-864-6985.
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