FILE - In this file photo made July 13, 2006, a P2-V Neptune air tanker drops retardant on a wildfire southwest of Elko, Nev. An air tanker dropping retardant on a remote wildfire along the Utah-Nevada line crashed Sunday, June 3, 2012, killing both crew members, authorities said. The pilots were flying a P-2V air tanker that is owned by Neptune Aviation Services of Missoula, Mont. (AP Photo/Elko Daily Free Press, Ross Andreson, file)

CALIENTE, Nev. (AP) - Fire officials say a wildfire burning on the Nevada-Utah border is now 90 percent contained and should be fully contained by Saturday.

Great Basin Incident Management Team officials say efforts Friday at the White Rock Fire will focus on mop-up and rehabilitating the fire line.

Officials have been able to cut back on staff needed to fight the fire, which has burned 6,251 acres.

Authorities say the wildfire was sparked Friday night by lightning on the eastern edge of Nevada's Lincoln County. It's burning in steep, rugged terrain and spread into Utah.

Two pilots from Boise, Idaho, were killed Sunday when their firefighting aircraft crashed during a mission to drop retardant on the blaze.

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