Haunted : a Bishop/Special Crimes Unit novel / Kay Hooper.

"When Deacon James's younger sister Melanie calls him, terrified, he goes to her aid in the small Georgia town of Sociable. What he finds is a scared young woman in the grip of what she insists is a paranormal nightmare--and murder. Two local men have been killed under mysterious circumstances. And Melanie is the prime suspect. Trinity Nichols left a high-stress job for quiet, small-town life. But news of the murders has left her--and the town--on edge, especially when there is nothing remotely ordinary about how the men died. And her investigation is yielding more than she bargained for, including a group of strangers who have descended on Sociable, some with abilities Trinity finds hard to believe, and agendas she refuses to trust. For some reason, they know a lot more than they should about what's happening in town. And what's happening is growing stranger by the minute. Now Trinity, Deacon, and this odd band of FBI agents must work together to solve a series of disturbances so incredible that Trinity, and the town of Sociable, will be changed forever. She just isn't certain who--or what--will be left standing when it's all over"--