At the local police station, Duanmu Huai found some clues. Initially, the chief wasn't fond of their visit. However, when he learned that they had been invited by Earl Best, he relaxed a bit.
According to the police, the fatalities were likely caused by a gang.
Their judgement was based on robust evidence.
According to the police autopsy reports, those killed had been bitten to death by some creature. The photographs in the magazine were unintentional; those were just some of the wounds. In fact, the perpetrator didn't just bite their necks, but tore them apart, as if they had been killed by a pack of wild beasts.
Although the autopsy records indeed indicate death by excessive bleeding, this bears no resemblance to the fabled vampire behavior— anyone would bleed to death from that many wounds.
As for the grave, it was indeed unearthed, but all traces suggest that it was dug up from the outside. If it were the work of a vampire, it would have been the inside.