KINGMAN, Ariz. (AP) - Crews concentrated Sunday on building fire lines around a 12,637-acre wildfire complex near this northwestern Arizona city and beefing up containment efforts in an area where the blaze had once threatened six homes.

Even though firefighters removed the threat to the homes, they worked to bolster protection lines there because the northeastern flank of the fire complex had the most recent advance toward houses, said Andy Mandell, a spokesman for the team battling the blaze.

Residents of six homes in the Golden Valley community, about 15 miles west of Kingman, were evacuated early Saturday, but were allowed to return home later in the day.

No homes or buildings were threatened Sunday by the four fires that make up the Black Mountain Complex. The fires began on Wednesday and Thursday when lightning storms moved through northwestern Arizona.

The complex was 80 percent contained. Full containment was expected by Monday evening. About 450 firefighters - aided by five helicopters and six airplanes - were battling the blaze.

“Containment has been moving along quite well,” Mandell said.