By Laura Zuckerman
SALMON, Idaho, Feb 26 (Reuters) - The FBI on Wednesday offered a $5,000 reward for help tracking down vandals who spray-painted anti-Mormon graffiti on three churches in a spree of defacements that left a predominantly Mormon town in southeastern Idaho shocked and puzzled.
The phrases and graphics - which included inverted crosses, "Die Mormons" and "Brigham Young was a rapist," an epithet against the early church leader - were emblazoned on doors and sidewalks at three Mormon meeting houses, or churches, in the town of Chubbuck.
The graffiti attacks, first noticed on Nov. 7, have bewildered the town of some 14,000 residents whose culture is largely shaped by the dominance of the Mormon faith, known officially as the Church of Jesus Christ of Latter-day Saints.
"It's an organization of faith, and what was said are potential threats," said William Facer, spokesman for the Federal Bureau of Investigation, which is seeking help in a multi-state investigation into what it regards as a hate crime.
Law enforcement officials are not aware of another recent case in which Mormon churches were the target of hate crimes in a region that encompasses Utah, Idaho and Montana, Facer said.
Idaho is second only to Utah in its percentage of members of the Mormon faith, whose worldwide adherents number 15 million.
Tensions over the church's influence in Utah and in contiguous Western states like Idaho and Nevada have periodically erupted in anti-Mormon outbursts, said Philip Barlow, professor of Mormon history and culture at Utah State University. (Reporting by Laura Zuckerman in Salmon, Idaho; Writing by Eric M. Johnson in Seattle; Editing by Janet Lawrence)