EVART - Police are searching for a fourth suspect in a criminal sexual conduct case under investigation in Evart. Brian Lindsley, 51, of Evart, is believed to have fled the state, but police are looking for information on his whereabouts, said Michigan State Police Det. Sgt. Gary Green. Lindsley is considered to be a suspect in a case involving three other men who sexually assaulted several juvenile girls. The Michigan State Police were contacted about the assaults by the Department of Human Services. Police investigation in the case began in the fall of 2011. "We're not sure how (DHS) became involved, but we conducted a joint investigation with them," Green said. "They look at different things, but we do it at the same time so we're not interviewing the victims too many times." The suspects and the victims are all "loosely related," Green said. Evart residents Bryan Keith Hill, 22, and Herman Bert Elston, 61, both were arraigned on several felony criminal sexual conduct charges on Thursday in Osceola County's 77th District Court. Hill is charged with two counts of first-degree criminal sexual conduct and two counts of third-degree criminal sexual conduct. He is held in Osceola County Jail on a $200,000 bond. Elston is charged with five counts of first-degree criminal sexual conduct and five counts of third-degree criminal sexual conduct. He is held on a $1 million bond. Both men are scheduled for preliminary examination at 1:30 p.m. on Aug. 23 in district court. A codefendant, Keldon Dennis, was arrested earlier this summer. He already has pleaded guilty to one count of first-degree criminal sexual conduct. Several other criminal sexual conduct charges were dismissed as part of the plea agreement. He is scheduled for sentencing at 9:15 a.m. on Aug. 24 in Osceola County's 49th Circuit Court. The investigation is ongoing and additional arrests are expected, according to state police. Anyone with information about this case is asked to contact the Michigan State Police post in Mount Pleasant at (989) 773-5951.