Police believe the killer was a gang member settling a score with a rival gang.警方认为，杀人犯是一团伙成员，当时正和敌对团伙算旧账。Police think that the killings may be a result of accounts being settled between local gangs.警方认为这些谋杀事件可能是当地黑帮互相清算旧账的结果。He is using his wealth and power to settle old scores.他凭借自己的财富和权力来算旧账。