BEIJING (AP) — State media say police in northeast China have arrested three men and one woman on suspicion of killing prostitutes and mutilating their bodies.

Xinhua News Agency says the four are accused of robbing and murdering 10 people across China from 1998 to 2004. Eight victims were prostitutes.

Xinhua on Tuesday quoted Sun Junting of Harbin city’s public security bureau as saying that each victim was mutilated.

It says the suspects lured prostitutes to rented houses and forced them to surrender bank cards and PIN numbers before killing them. Police estimate the group stole about $300,000 in total.

Police made the arrests in the city of Batou in the Inner Mongolia border region in November.