Roy Minami, the California Horse Racing Board's assistant executive director for more than 15 years, resigned his post this week.Reached by phone June 23, CHRB Executive Director Ingrid Fermin confirmed that Minami had been placed on an undisclosed administrative leave June 19."He had been on a short administrative leave, then decided to resign, I believe, on Wednesday (June 21)," she said.She declined to give a reason for the longtime racing board official's abrupt decision. "It's a personnel issue," she said.Minami, through the agency's public information officer Mike Marten, said he would have no comment. He came to the CHRB in March 1989 as an administrative manager and became assistant executive director in January 1991. Minami had been employed by the state for 31 years.He served as interim director of the agency in 1993 during a year long search to replace then-executive secretary Dennis Hutcheson and oversaw the CHRB again while a permanent replacement for Roy Wood was sought in 2004.Most recently, he had handled issues regarding California's rules on milkshaking and new digital fingerprint scanning technology for license applicants.