i need help were do i report abuse by a foster parent

the foster parent in question is a seductive person. the woman drinks constantly and smokes in front of the kids her parents live at the house and her dad is an alcoholic he drinks a case of 30 miller high lifes a day. the woman has beat and verbally abused the kids and yells and beats her own daughter. on 9/14/04 the grandfather and mother ganged up on the daughter verbally abused her then physically abused her minutes after the beating the daughter was throwing up blood the daughter was smart enough to record it. the mother also had her 21 year old son and his friend beat up a 10 year old foster son. she uses the kids as free slave labor. i believe this woman needs to be investigated and she needs to be revoked from foster care so if anyone can help me and tell me were to report this please respond