Let Us Prey - Detective Scott Murphy Series, #4

When famous celebrities around the Detroit area start turning up dead with bite marks that resemble vamire bites, Detective Scott Murphy and his partner Detective Hadeem McDougan are given the case. They are rushing to keep up with the dead bodies to track the killer. The only similarity is the blood letting from the victims, making them think of a past case where a cult was draining bood for their ceremony.
The only break in the case is a security video from a radio staion of the killers driving away in their car. The book is a novella, shorter than a novel but longer than a short story. It's the fourth bok in the series.